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5a836cfde60761001a2eb6b1
Copper
The major applications of copper are in electrical wires (60%), roofing and plumbing (20%) and industrial machinery (15%). Copper is mostly used as a pure metal, but when a higher hardness is required it is combined with other elements to make an alloy (5% of total use) such as brass and bronze. A small part of copper ...
What percentage of copper is used in paper wires?
{ "text": [], "answer_start": [] }
5a836cfde60761001a2eb6b2
Copper
The major applications of copper are in electrical wires (60%), roofing and plumbing (20%) and industrial machinery (15%). Copper is mostly used as a pure metal, but when a higher hardness is required it is combined with other elements to make an alloy (5% of total use) such as brass and bronze. A small part of copper ...
What percentage of copper is forbidden in roofing and plumbing?
{ "text": [], "answer_start": [] }
5a836cfde60761001a2eb6b3
Copper
The major applications of copper are in electrical wires (60%), roofing and plumbing (20%) and industrial machinery (15%). Copper is mostly used as a pure metal, but when a higher hardness is required it is combined with other elements to make an alloy (5% of total use) such as brass and bronze. A small part of copper ...
What percentage of copper is destroyed by industrial machinery?
{ "text": [], "answer_start": [] }
5a836cfde60761001a2eb6b4
Copper
The major applications of copper are in electrical wires (60%), roofing and plumbing (20%) and industrial machinery (15%). Copper is mostly used as a pure metal, but when a higher hardness is required it is combined with other elements to make an alloy (5% of total use) such as brass and bronze. A small part of copper ...
What property does combining copper with brass or bronze eliminate?
{ "text": [], "answer_start": [] }
5a836cfde60761001a2eb6b5
Copper
The major applications of copper are in electrical wires (60%), roofing and plumbing (20%) and industrial machinery (15%). Copper is mostly used as a pure metal, but when a higher hardness is required it is combined with other elements to make an alloy (5% of total use) such as brass and bronze. A small part of copper ...
What is a plant that copper is combined with to create a smoother texture?
{ "text": [], "answer_start": [] }
57097747200fba1400368029
Copper
The softness of copper partly explains its high electrical conductivity (59.6×106 S/m) and thus also high thermal conductivity, which are the second highest (to silver) among pure metals at room temperature. This is because the resistivity to electron transport in metals at room temperature mostly originates from scatt...
What is the explanation for copper's capacity for electrical conductivity?
{ "text": [ "The softness" ], "answer_start": [ 0 ] }
57097747200fba140036802a
Copper
The softness of copper partly explains its high electrical conductivity (59.6×106 S/m) and thus also high thermal conductivity, which are the second highest (to silver) among pure metals at room temperature. This is because the resistivity to electron transport in metals at room temperature mostly originates from scatt...
What metal has a higher thermal conductivity than copper?
{ "text": [ "silver" ], "answer_start": [ 161 ] }
57097747200fba140036802b
Copper
The softness of copper partly explains its high electrical conductivity (59.6×106 S/m) and thus also high thermal conductivity, which are the second highest (to silver) among pure metals at room temperature. This is because the resistivity to electron transport in metals at room temperature mostly originates from scatt...
What is the maximum premissible current density in open air of copper?
{ "text": [ "3.1×106 A/m2" ], "answer_start": [ 500 ] }
57097747200fba140036802c
Copper
The softness of copper partly explains its high electrical conductivity (59.6×106 S/m) and thus also high thermal conductivity, which are the second highest (to silver) among pure metals at room temperature. This is because the resistivity to electron transport in metals at room temperature mostly originates from scatt...
What occurs when copper is placed touching another metal?
{ "text": [ "corrosion" ], "answer_start": [ 655 ] }
57097747200fba140036802d
Copper
The softness of copper partly explains its high electrical conductivity (59.6×106 S/m) and thus also high thermal conductivity, which are the second highest (to silver) among pure metals at room temperature. This is because the resistivity to electron transport in metals at room temperature mostly originates from scatt...
What happens to copper if an electrical current gets too high?
{ "text": [ "it begins to heat excessively" ], "answer_start": [ 550 ] }
5a8342b6e60761001a2eb4d1
Copper
The softness of copper partly explains its high electrical conductivity (59.6×106 S/m) and thus also high thermal conductivity, which are the second highest (to silver) among pure metals at room temperature. This is because the resistivity to electron transport in metals at room temperature mostly originates from scatt...
What is the explanation for copper's capacity for nuclear conductivity?
{ "text": [], "answer_start": [] }
5a8342b6e60761001a2eb4d2
Copper
The softness of copper partly explains its high electrical conductivity (59.6×106 S/m) and thus also high thermal conductivity, which are the second highest (to silver) among pure metals at room temperature. This is because the resistivity to electron transport in metals at room temperature mostly originates from scatt...
What metal has an equal thermal conductivity to copper?
{ "text": [], "answer_start": [] }
5a8342b6e60761001a2eb4d3
Copper
The softness of copper partly explains its high electrical conductivity (59.6×106 S/m) and thus also high thermal conductivity, which are the second highest (to silver) among pure metals at room temperature. This is because the resistivity to electron transport in metals at room temperature mostly originates from scatt...
What is the only permissible current density in open air of copper?
{ "text": [], "answer_start": [] }
5a8342b6e60761001a2eb4d4
Copper
The softness of copper partly explains its high electrical conductivity (59.6×106 S/m) and thus also high thermal conductivity, which are the second highest (to silver) among pure metals at room temperature. This is because the resistivity to electron transport in metals at room temperature mostly originates from scatt...
What occurs when copper is placed apart from another metal?
{ "text": [], "answer_start": [] }
570978be200fba1400368039
Copper
Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Examples include Chuquicamata in Chile, Bingham Canyon Mine in Utah, United States and El Chino Mine in New Mexico, United States. According to the British Geological Survey, in 20...
In what form is copper extracted?
{ "text": [ "copper sulfides" ], "answer_start": [ 37 ] }
570978be200fba140036803a
Copper
Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Examples include Chuquicamata in Chile, Bingham Canyon Mine in Utah, United States and El Chino Mine in New Mexico, United States. According to the British Geological Survey, in 20...
From what types of mines is copper extracted?
{ "text": [ "open pit mines" ], "answer_start": [ 64 ] }
570978be200fba140036803b
Copper
Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Examples include Chuquicamata in Chile, Bingham Canyon Mine in Utah, United States and El Chino Mine in New Mexico, United States. According to the British Geological Survey, in 20...
What percentage of copper do the deposits have that are extracted?
{ "text": [ "0.4 to 1.0% copper" ], "answer_start": [ 120 ] }
570978be200fba140036803c
Copper
Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Examples include Chuquicamata in Chile, Bingham Canyon Mine in Utah, United States and El Chino Mine in New Mexico, United States. According to the British Geological Survey, in 20...
What country was the top producer of copper in 2005?
{ "text": [ "Chile" ], "answer_start": [ 324 ] }
570978be200fba140036803d
Copper
Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Examples include Chuquicamata in Chile, Bingham Canyon Mine in Utah, United States and El Chino Mine in New Mexico, United States. According to the British Geological Survey, in 20...
What is the name of the process being considered in Arizona that allows copper to be recovered?
{ "text": [ "in-situ leach process" ], "answer_start": [ 494 ] }
5a8356aae60761001a2eb5c9
Copper
Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Examples include Chuquicamata in Chile, Bingham Canyon Mine in Utah, United States and El Chino Mine in New Mexico, United States. According to the British Geological Survey, in 20...
What form is copper hidden?
{ "text": [], "answer_start": [] }
5a8356aae60761001a2eb5ca
Copper
Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Examples include Chuquicamata in Chile, Bingham Canyon Mine in Utah, United States and El Chino Mine in New Mexico, United States. According to the British Geological Survey, in 20...
What types of mines is copper invisible?
{ "text": [], "answer_start": [] }
5a8356aae60761001a2eb5cb
Copper
Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Examples include Chuquicamata in Chile, Bingham Canyon Mine in Utah, United States and El Chino Mine in New Mexico, United States. According to the British Geological Survey, in 20...
What percentage of mercury do the deposits have that are extracted?
{ "text": [], "answer_start": [] }
5a8356aae60761001a2eb5cc
Copper
Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Examples include Chuquicamata in Chile, Bingham Canyon Mine in Utah, United States and El Chino Mine in New Mexico, United States. According to the British Geological Survey, in 20...
What village was the top producer of copper in 2005?
{ "text": [], "answer_start": [] }
5a8356aae60761001a2eb5cd
Copper
Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Examples include Chuquicamata in Chile, Bingham Canyon Mine in Utah, United States and El Chino Mine in New Mexico, United States. According to the British Geological Survey, in 20...
What is the name of the process being considered in Australia that allows copper to be recovered?
{ "text": [], "answer_start": [] }
57097a0bed30961900e841ca
Copper
Like aluminium, copper is 100% recyclable without any loss of quality, regardless of whether it is in a raw state or contained in a manufactured product. In volume, copper is the third most recycled metal after iron and aluminium. It is estimated that 80% of the copper ever mined is still in use today. According to the...
What percent of copper is recyclable?
{ "text": [ "100%" ], "answer_start": [ 26 ] }
57097a0bed30961900e841cb
Copper
Like aluminium, copper is 100% recyclable without any loss of quality, regardless of whether it is in a raw state or contained in a manufactured product. In volume, copper is the third most recycled metal after iron and aluminium. It is estimated that 80% of the copper ever mined is still in use today. According to the...
What percentage of copper that has been mined is still being used today?
{ "text": [ "80%" ], "answer_start": [ 252 ] }
57097a0bed30961900e841cc
Copper
Like aluminium, copper is 100% recyclable without any loss of quality, regardless of whether it is in a raw state or contained in a manufactured product. In volume, copper is the third most recycled metal after iron and aluminium. It is estimated that 80% of the copper ever mined is still in use today. According to the...
What other metal besides copper is 100% recyclable?
{ "text": [ "aluminium" ], "answer_start": [ 5 ] }
57097a0bed30961900e841cd
Copper
Like aluminium, copper is 100% recyclable without any loss of quality, regardless of whether it is in a raw state or contained in a manufactured product. In volume, copper is the third most recycled metal after iron and aluminium. It is estimated that 80% of the copper ever mined is still in use today. According to the...
Name a metal that is recycled more often than copper?
{ "text": [ "aluminium" ], "answer_start": [ 220 ] }
57097a0bed30961900e841ce
Copper
Like aluminium, copper is 100% recyclable without any loss of quality, regardless of whether it is in a raw state or contained in a manufactured product. In volume, copper is the third most recycled metal after iron and aluminium. It is estimated that 80% of the copper ever mined is still in use today. According to the...
What is the amount of copper in use, per capita, globally?
{ "text": [ "35–55 kg" ], "answer_start": [ 443 ] }
5a836015e60761001a2eb61d
Copper
Like aluminium, copper is 100% recyclable without any loss of quality, regardless of whether it is in a raw state or contained in a manufactured product. In volume, copper is the third most recycled metal after iron and aluminium. It is estimated that 80% of the copper ever mined is still in use today. According to the...
What percent of copper is indestructible?
{ "text": [], "answer_start": [] }
5a836015e60761001a2eb61e
Copper
Like aluminium, copper is 100% recyclable without any loss of quality, regardless of whether it is in a raw state or contained in a manufactured product. In volume, copper is the third most recycled metal after iron and aluminium. It is estimated that 80% of the copper ever mined is still in use today. According to the...
What percentage of copper that has been mined is still in the air today?
{ "text": [], "answer_start": [] }
5a836015e60761001a2eb61f
Copper
Like aluminium, copper is 100% recyclable without any loss of quality, regardless of whether it is in a raw state or contained in a manufactured product. In volume, copper is the third most recycled metal after iron and aluminium. It is estimated that 80% of the copper ever mined is still in use today. According to the...
What other wood besides copper is 100% recyclable?
{ "text": [], "answer_start": [] }
5a836015e60761001a2eb620
Copper
Like aluminium, copper is 100% recyclable without any loss of quality, regardless of whether it is in a raw state or contained in a manufactured product. In volume, copper is the third most recycled metal after iron and aluminium. It is estimated that 80% of the copper ever mined is still in use today. According to the...
What metal is never recycled?
{ "text": [], "answer_start": [] }
5a836015e60761001a2eb621
Copper
Like aluminium, copper is 100% recyclable without any loss of quality, regardless of whether it is in a raw state or contained in a manufactured product. In volume, copper is the third most recycled metal after iron and aluminium. It is estimated that 80% of the copper ever mined is still in use today. According to the...
What is the amount of copper stolen, per capita, globally?
{ "text": [], "answer_start": [] }
57097f5e200fba1400368091
Copper
The metal's distinctive natural green patina has long been coveted by architects and designers. The final patina is a particularly durable layer that is highly resistant to atmospheric corrosion, thereby protecting the underlying metal against further weathering. It can be a mixture of carbonate and sulfate compounds i...
What pigment color is natural to copper?
{ "text": [ "green" ], "answer_start": [ 32 ] }
57097f5e200fba1400368092
Copper
The metal's distinctive natural green patina has long been coveted by architects and designers. The final patina is a particularly durable layer that is highly resistant to atmospheric corrosion, thereby protecting the underlying metal against further weathering. It can be a mixture of carbonate and sulfate compounds i...
What property does the final patina on cooper have?
{ "text": [ "highly resistant to atmospheric corrosion" ], "answer_start": [ 153 ] }
57097f5e200fba1400368093
Copper
The metal's distinctive natural green patina has long been coveted by architects and designers. The final patina is a particularly durable layer that is highly resistant to atmospheric corrosion, thereby protecting the underlying metal against further weathering. It can be a mixture of carbonate and sulfate compounds i...
What mixture of compounds is the final patina?
{ "text": [ "carbonate and sulfate" ], "answer_start": [ 287 ] }
57097f5e200fba1400368094
Copper
The metal's distinctive natural green patina has long been coveted by architects and designers. The final patina is a particularly durable layer that is highly resistant to atmospheric corrosion, thereby protecting the underlying metal against further weathering. It can be a mixture of carbonate and sulfate compounds i...
What conditions effect the mixture of carbonate and sulfate in copper?
{ "text": [ "environmental" ], "answer_start": [ 354 ] }
57097f5e200fba1400368095
Copper
The metal's distinctive natural green patina has long been coveted by architects and designers. The final patina is a particularly durable layer that is highly resistant to atmospheric corrosion, thereby protecting the underlying metal against further weathering. It can be a mixture of carbonate and sulfate compounds i...
What can be done to copper to give it a certain look?
{ "text": [ "finished" ], "answer_start": [ 465 ] }
5a836eeee60761001a2eb6d7
Copper
The metal's distinctive natural green patina has long been coveted by architects and designers. The final patina is a particularly durable layer that is highly resistant to atmospheric corrosion, thereby protecting the underlying metal against further weathering. It can be a mixture of carbonate and sulfate compounds i...
What pigment color is fake copper?
{ "text": [], "answer_start": [] }
5a836eeee60761001a2eb6d8
Copper
The metal's distinctive natural green patina has long been coveted by architects and designers. The final patina is a particularly durable layer that is highly resistant to atmospheric corrosion, thereby protecting the underlying metal against further weathering. It can be a mixture of carbonate and sulfate compounds i...
What property does the final patina on copper avoid?
{ "text": [], "answer_start": [] }
5a836eeee60761001a2eb6d9
Copper
The metal's distinctive natural green patina has long been coveted by architects and designers. The final patina is a particularly durable layer that is highly resistant to atmospheric corrosion, thereby protecting the underlying metal against further weathering. It can be a mixture of carbonate and sulfate compounds i...
What separation of compounds is the final patina?
{ "text": [], "answer_start": [] }
5a836eeee60761001a2eb6da
Copper
The metal's distinctive natural green patina has long been coveted by architects and designers. The final patina is a particularly durable layer that is highly resistant to atmospheric corrosion, thereby protecting the underlying metal against further weathering. It can be a mixture of carbonate and sulfate compounds i...
What conditions have no influence on the mixture of carbonate and sulfate in copper?
{ "text": [], "answer_start": [] }
5a836eeee60761001a2eb6db
Copper
The metal's distinctive natural green patina has long been coveted by architects and designers. The final patina is a particularly durable layer that is highly resistant to atmospheric corrosion, thereby protecting the underlying metal against further weathering. It can be a mixture of carbonate and sulfate compounds i...
What can be done to sugar to give it a certain look?
{ "text": [], "answer_start": [] }
57098140200fba14003680cb
Copper
Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of reactive oxygen species that damage DNA. Corresponding amounts of copper salts (30 mg/kg) are toxic in animals. A minimum dietary value for health...
What are copper salts sometimes used for?
{ "text": [ "suicide attempts" ], "answer_start": [ 59 ] }
57098140200fba14003680cc
Copper
Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of reactive oxygen species that damage DNA. Corresponding amounts of copper salts (30 mg/kg) are toxic in animals. A minimum dietary value for health...
When ingested in large amounts what does copper salts produce in humans?
{ "text": [ "copper toxicity" ], "answer_start": [ 95 ] }
57098140200fba14003680cd
Copper
Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of reactive oxygen species that damage DNA. Corresponding amounts of copper salts (30 mg/kg) are toxic in animals. A minimum dietary value for health...
What is the minimum amount of copper rabbits should have in their diet?
{ "text": [ "3 ppm" ], "answer_start": [ 373 ] }
57098140200fba14003680ce
Copper
Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of reactive oxygen species that damage DNA. Corresponding amounts of copper salts (30 mg/kg) are toxic in animals. A minimum dietary value for health...
What is a major benefit to rabbits having a higher concentration of copper in their diet?
{ "text": [ "growth rates" ], "answer_start": [ 539 ] }
57098140200fba14003680cf
Copper
Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of reactive oxygen species that damage DNA. Corresponding amounts of copper salts (30 mg/kg) are toxic in animals. A minimum dietary value for health...
What amount of copper salt is toxic in animals?
{ "text": [ "30 mg/kg" ], "answer_start": [ 254 ] }
5a8371c6e60761001a2eb71b
Copper
Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of reactive oxygen species that damage DNA. Corresponding amounts of copper salts (30 mg/kg) are toxic in animals. A minimum dietary value for health...
What are copper peppers sometimes used for?
{ "text": [], "answer_start": [] }
5a8371c6e60761001a2eb71c
Copper
Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of reactive oxygen species that damage DNA. Corresponding amounts of copper salts (30 mg/kg) are toxic in animals. A minimum dietary value for health...
When ingested in small amounts what does copper salts produce in humans?
{ "text": [], "answer_start": [] }
5a8371c6e60761001a2eb71d
Copper
Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of reactive oxygen species that damage DNA. Corresponding amounts of copper salts (30 mg/kg) are toxic in animals. A minimum dietary value for health...
What is the minimum amount of copper dragons should have in their diet?
{ "text": [], "answer_start": [] }
5a8371c6e60761001a2eb71e
Copper
Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of reactive oxygen species that damage DNA. Corresponding amounts of copper salts (30 mg/kg) are toxic in animals. A minimum dietary value for health...
What is a major benefit to dragons having a higher concentration of copper in their diet?
{ "text": [], "answer_start": [] }
5a8371c6e60761001a2eb71f
Copper
Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of reactive oxygen species that damage DNA. Corresponding amounts of copper salts (30 mg/kg) are toxic in animals. A minimum dietary value for health...
What amount of copper salt is toxic in robots?
{ "text": [], "answer_start": [] }
5709828fed30961900e84244
Copper
Britain's first use of brass occurred around the 3rd–2nd century BC. In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. Copper metallurgy was flourishing in South Ameri...
When did Britain first use brass?
{ "text": [ "3rd–2nd century BC" ], "answer_start": [ 49 ] }
5709828fed30961900e84245
Copper
Britain's first use of brass occurred around the 3rd–2nd century BC. In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. Copper metallurgy was flourishing in South Ameri...
Who were the first copper miners in North America?
{ "text": [ "Native Americans" ], "answer_start": [ 133 ] }
5709828fed30961900e84246
Copper
Britain's first use of brass occurred around the 3rd–2nd century BC. In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. Copper metallurgy was flourishing in South Ameri...
Where was native copper extracted with primitive tools between 800 and 1600?
{ "text": [ "Isle Royale" ], "answer_start": [ 211 ] }
5709828fed30961900e84247
Copper
Britain's first use of brass occurred around the 3rd–2nd century BC. In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. Copper metallurgy was flourishing in South Ameri...
What country had a strong copper production in 1000 AD
{ "text": [ "Peru" ], "answer_start": [ 340 ] }
5709828fed30961900e84248
Copper
Britain's first use of brass occurred around the 3rd–2nd century BC. In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. Copper metallurgy was flourishing in South Ameri...
When did commercial production of copper begin?
{ "text": [ "early 20th century" ], "answer_start": [ 548 ] }
5a836aeee60761001a2eb68b
Copper
Britain's first use of brass occurred around the 3rd–2nd century BC. In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. Copper metallurgy was flourishing in South Ameri...
When did Britain ban use of brass?
{ "text": [], "answer_start": [] }
5a836aeee60761001a2eb68c
Copper
Britain's first use of brass occurred around the 3rd–2nd century BC. In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. Copper metallurgy was flourishing in South Ameri...
Who were the only copper miners in North America?
{ "text": [], "answer_start": [] }
5a836aeee60761001a2eb68d
Copper
Britain's first use of brass occurred around the 3rd–2nd century BC. In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. Copper metallurgy was flourishing in South Ameri...
Where was native copper hidden with primitive tools between 800 and 1600?
{ "text": [], "answer_start": [] }
5a836aeee60761001a2eb68e
Copper
Britain's first use of brass occurred around the 3rd–2nd century BC. In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. Copper metallurgy was flourishing in South Ameri...
What country stopped a strong copper production in 1000 AD?
{ "text": [], "answer_start": [] }
5a836aeee60761001a2eb68f
Copper
Britain's first use of brass occurred around the 3rd–2nd century BC. In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. Copper metallurgy was flourishing in South Ameri...
When did commercial production of copper end?
{ "text": [], "answer_start": [] }
5709844f200fba1400368107
Copper
There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mC...
How many isotopes are there of copper?
{ "text": [ "29" ], "answer_start": [ 10 ] }
5709844f200fba1400368108
Copper
There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mC...
What are the two stable isotopes of cooper?
{ "text": [ "63Cu and 65Cu" ], "answer_start": [ 33 ] }
5709844f200fba1400368109
Copper
There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mC...
Which isotope makes up about 69% of natural copper?
{ "text": [ "63Cu" ], "answer_start": [ 64 ] }
5709844f200fba140036810a
Copper
There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mC...
What is the half life of the copper isotope 68mCu?
{ "text": [ "3.8 minutes" ], "answer_start": [ 360 ] }
5709844f200fba140036810b
Copper
There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mC...
What is the half life of the copper isotope 67Cu?
{ "text": [ "61.83 hours" ], "answer_start": [ 247 ] }
5a83518ce60761001a2eb56d
Copper
There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mC...
How many isotopes are missing in copper?
{ "text": [], "answer_start": [] }
5a83518ce60761001a2eb56e
Copper
There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mC...
What are the two dangerous isotopes of copper?
{ "text": [], "answer_start": [] }
5a83518ce60761001a2eb56f
Copper
There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mC...
Which isotope makes up about 74% of natural copper?
{ "text": [], "answer_start": [] }
5a83518ce60761001a2eb570
Copper
There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mC...
What is the half life of the supernatural isotope 68mCu?
{ "text": [], "answer_start": [] }
5a83518ce60761001a2eb571
Copper
There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mC...
What is the orbital period of the copper isotope 67Cu?
{ "text": [], "answer_start": [] }
5709867b200fba1400368143
Copper
The alloy of copper and nickel, called cupronickel, is used in low-denomination coins, often for the outer cladding. The US 5-cent coin called a nickel consists of 75% copper and 25% nickel and has a homogeneous composition. The alloy consisting of 90% copper and 10% nickel is remarkable for its resistance to corrosion...
What is the alloy of copper and nickel called?
{ "text": [ "cupronickel" ], "answer_start": [ 39 ] }
5709867b200fba1400368144
Copper
The alloy of copper and nickel, called cupronickel, is used in low-denomination coins, often for the outer cladding. The US 5-cent coin called a nickel consists of 75% copper and 25% nickel and has a homogeneous composition. The alloy consisting of 90% copper and 10% nickel is remarkable for its resistance to corrosion...
what is the alloy of copper and nickel used for?
{ "text": [ "low-denomination coins" ], "answer_start": [ 63 ] }
5709867b200fba1400368145
Copper
The alloy of copper and nickel, called cupronickel, is used in low-denomination coins, often for the outer cladding. The US 5-cent coin called a nickel consists of 75% copper and 25% nickel and has a homogeneous composition. The alloy consisting of 90% copper and 10% nickel is remarkable for its resistance to corrosion...
What is the metal composition of a US nickel?
{ "text": [ "75% copper and 25% nickel" ], "answer_start": [ 164 ] }
5709867b200fba1400368146
Copper
The alloy of copper and nickel, called cupronickel, is used in low-denomination coins, often for the outer cladding. The US 5-cent coin called a nickel consists of 75% copper and 25% nickel and has a homogeneous composition. The alloy consisting of 90% copper and 10% nickel is remarkable for its resistance to corrosion...
What extraordinary property does the alloy made up of 90% copper and 10% nickel possess?
{ "text": [ "resistance to corrosion" ], "answer_start": [ 297 ] }
5709867b200fba1400368147
Copper
The alloy of copper and nickel, called cupronickel, is used in low-denomination coins, often for the outer cladding. The US 5-cent coin called a nickel consists of 75% copper and 25% nickel and has a homogeneous composition. The alloy consisting of 90% copper and 10% nickel is remarkable for its resistance to corrosion...
What color is created when the alloys of copper and aluminium are combined?
{ "text": [ "golden" ], "answer_start": [ 439 ] }
5a836094e60761001a2eb62f
Copper
The alloy of copper and nickel, called cupronickel, is used in low-denomination coins, often for the outer cladding. The US 5-cent coin called a nickel consists of 75% copper and 25% nickel and has a homogeneous composition. The alloy consisting of 90% copper and 10% nickel is remarkable for its resistance to corrosion...
What is the liquid of copper and nickel called?
{ "text": [], "answer_start": [] }
5a836094e60761001a2eb630
Copper
The alloy of copper and nickel, called cupronickel, is used in low-denomination coins, often for the outer cladding. The US 5-cent coin called a nickel consists of 75% copper and 25% nickel and has a homogeneous composition. The alloy consisting of 90% copper and 10% nickel is remarkable for its resistance to corrosion...
What is the liquid of copper and nickel never used for?
{ "text": [], "answer_start": [] }
5a836094e60761001a2eb631
Copper
The alloy of copper and nickel, called cupronickel, is used in low-denomination coins, often for the outer cladding. The US 5-cent coin called a nickel consists of 75% copper and 25% nickel and has a homogeneous composition. The alloy consisting of 90% copper and 10% nickel is remarkable for its resistance to corrosion...
What is the wood composition of a US nickel?
{ "text": [], "answer_start": [] }
5a836094e60761001a2eb632
Copper
The alloy of copper and nickel, called cupronickel, is used in low-denomination coins, often for the outer cladding. The US 5-cent coin called a nickel consists of 75% copper and 25% nickel and has a homogeneous composition. The alloy consisting of 90% copper and 10% nickel is remarkable for its resistance to corrosion...
What mundane property does the alloy made up of 90% copper and 10% nickel possess?
{ "text": [], "answer_start": [] }
5a836094e60761001a2eb633
Copper
The alloy of copper and nickel, called cupronickel, is used in low-denomination coins, often for the outer cladding. The US 5-cent coin called a nickel consists of 75% copper and 25% nickel and has a homogeneous composition. The alloy consisting of 90% copper and 10% nickel is remarkable for its resistance to corrosion...
What color is created when the alloys of copper and aluminium are apart?
{ "text": [], "answer_start": [] }
5709880eed30961900e842a4
Copper
Polyols, compounds containing more than one alcohol functional group, generally interact with cupric salts. For example, copper salts are used to test for reducing sugars. Specifically, using Benedict's reagent and Fehling's solution the presence of the sugar is signaled by a color change from blue Cu(II) to reddish co...
What is the name of the componds that has more than one alcohol functional group?
{ "text": [ "Polyols" ], "answer_start": [ 0 ] }
5709880eed30961900e842a5
Copper
Polyols, compounds containing more than one alcohol functional group, generally interact with cupric salts. For example, copper salts are used to test for reducing sugars. Specifically, using Benedict's reagent and Fehling's solution the presence of the sugar is signaled by a color change from blue Cu(II) to reddish co...
What are copper salts used to test?
{ "text": [ "reducing sugars" ], "answer_start": [ 155 ] }
5709880eed30961900e842a6
Copper
Polyols, compounds containing more than one alcohol functional group, generally interact with cupric salts. For example, copper salts are used to test for reducing sugars. Specifically, using Benedict's reagent and Fehling's solution the presence of the sugar is signaled by a color change from blue Cu(II) to reddish co...
How is the presence of sugar shown by using Benedict's reagent and Fehling's solution?
{ "text": [ "color change" ], "answer_start": [ 277 ] }
5709880eed30961900e842a7
Copper
Polyols, compounds containing more than one alcohol functional group, generally interact with cupric salts. For example, copper salts are used to test for reducing sugars. Specifically, using Benedict's reagent and Fehling's solution the presence of the sugar is signaled by a color change from blue Cu(II) to reddish co...
What color does the copper salts turn to using Benedict's reagent and Fehling's solution if sugar is present?
{ "text": [ "reddish" ], "answer_start": [ 310 ] }
5709880eed30961900e842a8
Copper
Polyols, compounds containing more than one alcohol functional group, generally interact with cupric salts. For example, copper salts are used to test for reducing sugars. Specifically, using Benedict's reagent and Fehling's solution the presence of the sugar is signaled by a color change from blue Cu(II) to reddish co...
What does Schweizer's reagent dissolve?
{ "text": [ "cellulose" ], "answer_start": [ 424 ] }
5a836387e60761001a2eb64d
Copper
Polyols, compounds containing more than one alcohol functional group, generally interact with cupric salts. For example, copper salts are used to test for reducing sugars. Specifically, using Benedict's reagent and Fehling's solution the presence of the sugar is signaled by a color change from blue Cu(II) to reddish co...
What is the name of the compounds that have no alcohol functional group?
{ "text": [], "answer_start": [] }
5a836387e60761001a2eb64e
Copper
Polyols, compounds containing more than one alcohol functional group, generally interact with cupric salts. For example, copper salts are used to test for reducing sugars. Specifically, using Benedict's reagent and Fehling's solution the presence of the sugar is signaled by a color change from blue Cu(II) to reddish co...
What are copper salts used to burn?
{ "text": [], "answer_start": [] }
5a836387e60761001a2eb64f
Copper
Polyols, compounds containing more than one alcohol functional group, generally interact with cupric salts. For example, copper salts are used to test for reducing sugars. Specifically, using Benedict's reagent and Fehling's solution the presence of the sugar is signaled by a color change from blue Cu(II) to reddish co...
How is the presence of sugar hidden by using Benedict's reagent and Fehling's solution?
{ "text": [], "answer_start": [] }
5a836387e60761001a2eb650
Copper
Polyols, compounds containing more than one alcohol functional group, generally interact with cupric salts. For example, copper salts are used to test for reducing sugars. Specifically, using Benedict's reagent and Fehling's solution the presence of the sugar is signaled by a color change from blue Cu(II) to reddish co...
What color does the copper salts turn to using Benedict's reagent and Fehling's solution if dust is present?
{ "text": [], "answer_start": [] }
5a836387e60761001a2eb651
Copper
Polyols, compounds containing more than one alcohol functional group, generally interact with cupric salts. For example, copper salts are used to test for reducing sugars. Specifically, using Benedict's reagent and Fehling's solution the presence of the sugar is signaled by a color change from blue Cu(II) to reddish co...
What does Schweizer's reagent grow?
{ "text": [], "answer_start": [] }
57098a0b200fba140036816b
Copper
Alloying copper with tin to make bronze was first practiced about 4000 years after the discovery of copper smelting, and about 2000 years after "natural bronze" had come into general use[citation needed]. Bronze artifacts from the Vinča culture date to 4500 BC. Sumerian and Egyptian artifacts of copper and bronze alloy...
What started about 4000 years after copper smelting was discovered?
{ "text": [ "Alloying copper with tin to make bronze" ], "answer_start": [ 0 ] }
57098a0b200fba140036816c
Copper
Alloying copper with tin to make bronze was first practiced about 4000 years after the discovery of copper smelting, and about 2000 years after "natural bronze" had come into general use[citation needed]. Bronze artifacts from the Vinča culture date to 4500 BC. Sumerian and Egyptian artifacts of copper and bronze alloy...
What are the first datings of Bronze artifacts from the Vinca culture?
{ "text": [ "4500 BC" ], "answer_start": [ 253 ] }
57098a0b200fba140036816d
Copper
Alloying copper with tin to make bronze was first practiced about 4000 years after the discovery of copper smelting, and about 2000 years after "natural bronze" had come into general use[citation needed]. Bronze artifacts from the Vinča culture date to 4500 BC. Sumerian and Egyptian artifacts of copper and bronze alloy...
When did the Bronze Age began in Southeastern Europe?
{ "text": [ "3700–3300 BC" ], "answer_start": [ 390 ] }
57098a0b200fba140036816e
Copper
Alloying copper with tin to make bronze was first practiced about 4000 years after the discovery of copper smelting, and about 2000 years after "natural bronze" had come into general use[citation needed]. Bronze artifacts from the Vinča culture date to 4500 BC. Sumerian and Egyptian artifacts of copper and bronze alloy...
What was the transition between the Neolithic period and the bronze age called?
{ "text": [ "Chalcolithic" ], "answer_start": [ 632 ] }
57098a0b200fba140036816f
Copper
Alloying copper with tin to make bronze was first practiced about 4000 years after the discovery of copper smelting, and about 2000 years after "natural bronze" had come into general use[citation needed]. Bronze artifacts from the Vinča culture date to 4500 BC. Sumerian and Egyptian artifacts of copper and bronze alloy...
What is an alloy of copper and zinc?
{ "text": [ "Brass" ], "answer_start": [ 855 ] }
5a836761e60761001a2eb677
Copper
Alloying copper with tin to make bronze was first practiced about 4000 years after the discovery of copper smelting, and about 2000 years after "natural bronze" had come into general use[citation needed]. Bronze artifacts from the Vinča culture date to 4500 BC. Sumerian and Egyptian artifacts of copper and bronze alloy...
What started about 3000 years after copper smelting was discovered?
{ "text": [], "answer_start": [] }