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Recently I've been trying to answer the question 10-13 (c) of 9th edition of *Fundamentals of Analytical Chemistry of Skoog et al*. Comparing my answers with the student manual , I realized that my numbers didn't agree to the amount of $\mu$ of solution calculated by the book.
Here's the full question:
> Use activ... |
Are molecular properties robust towards manipulations? |
I recently participated in an experiment where I need to calculated the reaction orders and the reaction constant of the reaction:
$$\ce{8 Na2S2O3(aq) + 16 HCl(aq) -> S8(s) + 8 SO2(g) + 16 NaCl(aq) + 8 H2O(l)}$$
by measuring time until the solution becomes too turbid for light to travel through the fluid. Calcu... |
Consider the dehydration reaction of the following compounds with conc. $\ce{H2SO4}$:<br>
>(a) Tert-butyl alcohol<br>
>(b) 3-Methylbut-2-enol<br>
Consider the protonation of the $\ce{OH}$ group followed by the removal of water molecule. In (a), we get a tertiary carbocation whereas in (b) we get a primary allylic ... |
Although the general trend $\mathrm{s} < \mathrm{p} < \mathrm{sp}^n$ makes sense, these magic numbers $1.73$, $1.93$, $1.99$, and $2.00$ seem to have just been pulled out of a hat. If these are really "approximate strengths of bonds", a good book would justify these by showing *which* bonds they use to come up with the... |
Although the general trend $\mathrm{s} < \mathrm{p} < \mathrm{sp}^n$ makes sense, these magic numbers $1.73$, $1.93$, $1.99$, and $2.00$ seem to have just been pulled out of a hat. If these are really "approximate strengths of bonds", a good book would justify these by showing *which* bonds they use to come up with the... |
Consider the dehydration reaction of the following compounds with conc. $\ce{H2SO4}$:<br>
>(a) Tert-butyl alcohol<br>
>(b) 3-Methylbut-2-en-1-ol<br>
Consider the protonation of the $\ce{OH}$ group followed by the removal of water molecule. In (a), we get a tertiary carbocation whereas in (b) we get a primary allyl... |
I've made aluminum powder in a ball mill a few times, but my last batch began to smoke and caught on fire soon after I poured it from the tumbler. Nothing unusual was afoot. It was poured into a paper plate. The ball mill aggregate had steel bearings and a few rounded rocks, same as I had used before.
The only differ... |
I tried to extract hydrogen for my kid's birthday, by mixing caustic soda with water and aluminum foil (mixed in a glass bottle). A lot of heat and (hopefully)hydrogen was released.
However, within 2-3 hours, the balloons started losing altitude and began falling down. I supposed it was caused by losing the gas slowl... |
I recently conducted a simple experiment for school involving the electrolysis of water.
I changed the concentrations of an ionic compound to determine its effect on the rate at which the products of the lysis of water are formed. I used graphite rods for the electrodes. These shed quite heavily.
I noted this down ... |
Is it possible for graphite which has shed off metal rods during water electrolysis to bond with the hydrogen being produced to form hydrocarbons? |
I want to purify all primary amines containing compounds in a complex mixture (cell-extracted metabolites). I'm unaware of any published methods to do so. So I am thinking of making my own using a reversible Schiff base immobilization.
My input is a 1 mL metabolite extract that contains hundreds of compounds with a ... |
I recently participated in an experiment where I need to calculated the reaction orders and the reaction constant of the reaction:
$$\ce{8 Na2S2O3(aq) + 16 HCl(aq) -> S8(s) + 8 SO2(g) + 16 NaCl(aq) + 8 H2O(l)}$$
by measuring time until the solution becomes too turbid for light to travel through the fluid. Calcu... |
Electrons of opposite spin create magnetic fields that are opposite to each other.So,is it possible that,'such electron pairs attract each other' or 'they distract each other less than electron of same spin'? |
do electrons of opposite spin attract each other? |
Just looking around at the reactivity of aluminum, and wondered:
> Is if possible to reduce aluminum hydroxide to aluminum metal, by using a sacrificial magnesium electrode in a single displacement reaction?
I checked my revision of redox charts and it looks like it should work. So, what am I missing? Does it wor... |
Consider the dehydration reaction of the following compounds with conc. $\ce{H2SO4}$:<br>
>(a) Tert-butyl alcohol<br>
>(b) 3-Methylbut-2-en-1-ol<br>
Consider the protonation of the $\ce{OH}$ group followed by the removal of a water molecule. In (a), we get a tertiary carbocation whereas in (b) we get a primary all... |
Electrons of opposite spin create magnetic fields that are opposite to each other. So, is it possible that, 'such electron pairs attract each other' or ' they distract each other less than electron of same spin'? Thanks. |
Do electrons of opposite spin attract each other? |
I am an engineering student who loves physics but didn't quite enjoy chemistry.
**a.** When I was in high school chemistry to me was something not as inspiring as physics but in which I couldn't solve problems well. Things looked no more than the arithmetics, but I got the answers wrong.
**b.** Reading university... |
Why is chemistry meaningful? |
> Why isn't chemistry as science-looking as other natural sciences?
For some reason chemistry is often taught badly (Khan Academy is probably the best place to start if you want to study the subject on your own). And there is less _interesting_ information about chemistry on the internet relative to other discipline... |
> Why isn't chemistry as science-looking as other natural sciences?
For some reason chemistry is often taught badly (Khan Academy is probably the best place to start if you want to study the subject on your own). And there is less _interesting_ information about chemistry on the internet relative to other discipline... |
> Why isn't chemistry as science-looking as other natural sciences?
For some reason chemistry is often taught badly (Khan Academy is probably the best place to start if you want to study the subject on your own). And there is less _interesting_ information about chemistry on the internet relative to other discipline... |
What is the essence of chemistry? |
> Why isn't chemistry as science-looking as other natural sciences?
For some reason chemistry is often taught badly (Khan Academy is probably the best place to start if you want to study the subject on your own). And there is less _interesting_ information about chemistry on the internet relative to other discipline... |
> Why isn't chemistry as science-looking as other natural sciences?
For some reason chemistry is often taught badly (Khan Academy is probably the best place to start if you want to study the subject on your own). And there is less _interesting_ information about chemistry on the internet relative to other discipline... |
I was thinking about an organic chemistry problem a few days ago but reached a dead end. There were 2 parts to this question.
The first was thinking about the isomers of 'C4H3X2' [where X could be anything like a halogen or a deuterium etc].
I came up with the following 7 isomers:
[![enter image description... |
Consider the dehydration reaction of the following compounds with conc. $\ce{H2SO4}$:<br>
>(a) Tert-butyl alcohol<br>
>(b) 3-Methylbut-2-en-1-ol<br>
Consider the protonation of the $\ce{OH}$ group followed by the removal of a water molecule. In (a), we get a tertiary carbocation whereas in (b) we get a primary all... |
I was thinking about an organic chemistry problem a few days ago but reached a dead end. There were 2 parts to this question.
The first was thinking about the isomers of 'C3H4X2' [where X could be anything like a halogen or a deuterium etc].
I came up with the following 7 isomers:
[![enter image description... |
I am an engineering student who loves physics but didn't quite enjoy chemistry.
**a.** When I was in high school chemistry to me was something not as inspiring as physics but in which I couldn't solve problems well. Things looked no more than the arithmetics, but I got the answers wrong.
**b.** Reading university... |
According to Graham's law, we can calculate de average speed of gasses by using the formula
$$v^2=\frac{3RT}{M}$$
I tried to use this [simulation][1] and got these data by keeping same particles amount and increasing the temperature:
[![enter image description here][2]][2]
But, shouldn't be the speed ($... |
According to Graham's law, we can calculate de average speed of gasses by using the formula
$$v^2=\frac{3RT}{M}$$
I tried to use this [simulation][1] and got these data by keeping same particles amount and increasing the temperature(average speed(m/s) - temperatura(°C)):
[![enter image description here][2]][... |
Interesting question but keep in mind that it is normal to dislike a subject. You don't *have to* like chemistry. Many people loathe physics and mathematics. The world is not affected. I am sure your experience is limited to general chemistry and Oxtoby. In statistical terms, one cannot and should not trust a single sa... |
Glowing [press releases][1] and [news articles][2] in 2015 proclaimed a new allotrope of carbon. However, even the [journal article][3] is light on chemical detail (e.g. no structural formula).
- What is its bond structure?
- Why is it ferromagnetic? fluorescent? harder than diamond? etc?
- Or is it an erroneou... |
According to Graham's law, we can calculate de average speed of gasses by using the formula
$$v^2=\frac{3RT}{M}$$
I tried to use this [simulation][1] and got these data by keeping same particles amount and increasing the temperature(average speed(m/s) - temperatura(°C)):
| T in C | V in m/s |
|--... |
I was thinking about an organic chemistry problem a few days ago but reached a dead end. There were 2 parts to this question.
The first was thinking about the isomers of 'C3H4X2' [where X could be anything like a halogen or a deuterium etc].
I came up with the following 7 isomers:
[![enter image description... |
I'm not sure what you mean by 90% and 10%. If you mean 90% yield (i.e. 90% or more of the bicarbonate ions in sodium bicarbonate will become carbon dioxide), then yes, that will happen if there is enough acid. How much is enough acid? We'll get to that in a minute. If you mean something else, like 90% of the mass of th... |
does DIBAl-H reduce tertiary alcohol? i was reading an article and i came across this reaction but couldn't figure out how the final compound is formed [![][1]][1]
[1]: https://i.stack.imgur.com/LmriX.png |
does DIBAl-H reduces alcohol? |
I was reading about active transport in membranes where ATP is used. ATP "reacts" with the protein pump and converts into ADP and also make a conformational change to the pump. Now this conformational change can transport molecules from low concentrations to high concentrations areas i.e. opposite in their concentratio... |
What favors the active transport in a membrane? |
I was reading about active transport in membranes where ATP is used. ATP "reacts" with the protein pump and converts into ADP and also make a conformational change to the pump. Now this conformational change can transport molecules from low concentrations to high concentrations areas i.e. opposite in their concentratio... |
>Is my pipette a blow-out pipette?
I suspect that it is a blow-out pipette, though the double lines aren't rings. My guess is it is a TC blow-out pipette. Yet, I wonder, how am I supposed to know? I also have another one with a single dark band on the top.
[![a pipette][1]][1]
[![enter image description here... |
Is my pipette a blow-out pipette?
I suspect that it is a blow-out pipette, though the double lines aren't rings. My guess is it is a TC blow-out pipette. It's a big 50 mL pipette, longer than my arm.
I wonder, how am I supposed to know? I also have another one with a single dark band on the top.
[![pipette to... |
How to identify a blow-out pipette? |
>Is my pipette a blow-out pipette?
[![A picture of my pipette][1]][1]
I suspect that it is a blow-out pipette, though the double lines aren't rings. My guess is it is a TC blow-out pipette. Yet, I wonder, how am I supposed to know? I also have another one with a single dark band on the top.
EDIT: My pipett... |
How to identify a blow-out pipette? |
Interesting question but keep in mind that it is normal to dislike a subject. You don't *have to* like chemistry. Many people loathe physics and mathematics. The world is not affected. I am sure your experience is limited to general chemistry and Oxtoby. In statistical terms, one cannot and should not trust a single sa... |
Is my pipette a blow-out pipette?
I suspect that it is a blow-out pipette, though the double lines aren't rings. My guess is it is a TC blow-out pipette. It's a big 50 mL pipette, longer than my arm.
I wonder, how am I supposed to know? I also have another one with a single dark band on the top.
[ says this....:
>For a commonplace example based on the facts that the masses of a mole of water, a mole of hydrogen ions, ... |
Most places tell me that the number on the pH scale tells you the number of dissociated ions, in moles, per liter of substance. But, Wikipedia's article [pH](https://en.wikipedia.org/wiki/PH#Definition_and_measurement) says this....:
>For a commonplace example based on the facts that the masses of a mole of water... |
Most places tell me that the number on the pH scale tells you the number of dissociated ions, in moles, per liter of substance. But, Wikipedia's article [pH](https://en.wikipedia.org/wiki/PH#Definition_and_measurement) says this....:
>For a commonplace example based on the facts that the masses of a mole of water... |
Most places tell me that the number on the pH scale tells you the number of dissociated ions, in moles, per liter of substance. But, Wikipedia's article [pH](https://en.wikipedia.org/wiki/PH#Definition_and_measurement) says this....:
>... For a commonplace example based on the facts that the masses of a mole of w... |
While studying about the ***Nomenclature of Coordination Compounds*** I came to know that
>While writing formulae of **Mononuclear Coordination entities** polyatomic ligands are enclosed in parenthesis and also their abbreviations.
But while naming the entities should I follow the same rule?
Like for $\ce{[Ni(... |
I am an engineering student who loves physics but didn't quite enjoy chemistry.
**a.** When I was in high school chemistry to me was something not as inspiring as physics but in which I couldn't solve problems well. Things looked no more than the arithmetics, but I got the answers wrong.
**b.** Reading university... |
Most places tell me that the number on the pH scale tells you the number of dissociated ions, in moles, per liter of substance. But, Wikipedia's article [pH](https://en.wikipedia.org/wiki/PH#Definition_and_measurement) says this....:
>... For a commonplace example based on the facts that the masses of a mole of w... |
I am working on a project of analyzing heavy metals in milk samples using flame AAS. So far I have only analyzed cadmium and the results of spiked and unspiked have large differences. I was wondering if something went wrong with my digestion procedure. The procedure is listed as followed:
- 2g of milk sample, add 5... |
According to Haley and Rhodes, neostigmine bromide (alternatively known as Prostigmine) has an LD50 in mice of around 0.165 mg/kg by IV injection. Pubchem claims that this is also the LD50 for neostigmine iodide. According to Pubchem, [Ro-1837][1], the analog of neostigmine in which the ester oxygen is replaced with su... |
Why are S-thiocarbamates less toxic than carbamates? |
does DIBAl-H reduce tertiary alcohol? i was reading an article " https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.201206560 " and i came across this reaction but couldn't figure out how the final compound is formed [![][1]][1]
[1]: https://i.stack.imgur.com/LmriX.png |
does DIBAl-H reduces alcohol? i was reading an article " https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.201206560 " and i came across this reaction but couldn't figure out how the final compound is formed [![][1]][1]
[1]: https://i.stack.imgur.com/LmriX.png |
Does DIBAL-H reduces alcohol? I was reading an article by Rentsch and Kalesse \[[1](https://doi.org/10.1002/anie.201206560)\] and I came across this reaction, but could not figure out how the final compound is formed:
> [![Synthesis of 4][1]][1]
### Reference
1. Rentsch, A.; Kalesse, M. The Total Synthesis ... |
Does DIBAl-H reduce alcohol? |
The book I have looks like it says copper chloride is formed at the anode and copper oxide at the cathode, is that correct? |
What happens when salt water is electrolyzed with a carbon anode and a copper cathode? |
I haven't really comed across a reagent NaNH2/NH3 in my whole session, Well i have got B which is CH3-CH(Br)-CH2-Br but then how do i proceed next how will my substrate react with that reagent and what product will i achieve, does anybody have a fair idea?!
[![enter image description here][1]][1]
[1]: htt... |
I heard that copper oxide is formed on the cathode and copper chloride is formed on the anode, is this correct?
I don't have much knowledge of chemistry, so I can't find out much by searching on Google. |
> In the following sequence of reactions:
>
> $$\ce{CH3-CH2-CH2-I ->[\text{Alc.}~KOH] \textbf{A} ->[Br2] \textbf{B} ->[NaNH2/NH3] \textbf{C}}$$
>
> the product **C** is:
>
> (A) alkene
> (B) alkanol
> (C) alkyne
> (D) alkylamine
I haven't really came across a reagent $\ce{NaNH2}/\ce{NH3}$ in my whol... |
This needs a little background so I will be showing you a question from one of my Organic Chemistry problem books:-
[![][1]][1]
[1]: https://i.stack.imgur.com/AvI3q.jpg
Now, the book shows the answer as Option (c) which is Paracetamol.
I tried to work out the mechanism and I was pondering over the fact th... |
While treating 4-aminophenol with acetic anhydride why does the reaction stop at Paracetamol and does not undergo esterification with acetic acid? |
Does DIBAL-H reduce alcohol? |
Does DIBAL-H reduce alcohol? I was reading an article by Rentsch and Kalesse \[[1](https://doi.org/10.1002/anie.201206560)\] and I came across this reaction, but could not figure out how the final compound is formed:
> [![Synthesis of 4][1]][1]
### Reference
1. Rentsch, A.; Kalesse, M. The Total Synthesis o... |
What happens when salt water is electrolyzed with a copper anode and a copper cathode? |
What estimation of the dynamic viscosity $\eta = f(T)$ $([\eta] = \pu{Pa·s})$ of the gas mixture components would you recommend during adsorption at a low temperature, approx. $\pu{293 K}$ to $\pu{333 K},$ and a relatively low pressure?
Gas mixture contains $\ce{N2}$ (the major component), $\ce{CO2}$ and $\ce{H2O}$... |
Is my pipette a blow-out pipette?
I suspect that it is a blow-out pipette, though the double lines aren't rings. My guess is it is a TC blow-out pipette. It's a big 50 mL pipette, longer than my arm.
I wonder, how am I supposed to know? I also have another one with a single dark band on the top.
EDIT: This [v... |
When reading about TNT (trinitrotoluene), I noticed that the aromatic ring has still 2 carbon atoms left for two more possible nitro groups ($\ce{−NO2}$), which would get you tetra- or pentanitrotoluene. \
**2-methyl-1,3,5-trinitrobenzene (TNT):**
$$
\ce{\phantom{H3}CH3\phantom{=C}} \\
\ce{|\phantom{=C}} \\
\ce{\p... |
Are tetra- and pentanitrotoluene better explosives than TNT? |
When reading about TNT (trinitrotoluene), I noticed that the aromatic ring has still 2 carbon atoms left for two more possible nitro groups ($\ce{−NO2}$), which would get you tetra- or pentanitrotoluene.
[![Unsubstituted carbon atoms in TNT][1]][1]
The amount of available oxygen in TNT is not enough for a complet... |
I came across a question in a textbook [Chemistry Live, Declan Kennedy].
Draw the structural formula for the compound $\ce{1,3,5-trimethylhex-3-ene}$
My issue is with the 1-methyl part.
Is this compound not just the same as $\ce{2,4-dimethylhept-3-ene}$?
|
Can x = 1 for a compound of the form x-methyl-3-hexane? |
I came across a question in a textbook *Chemistry Live* by Declan Kennedy:
> Draw the structural formula for the compound 1,3,5-trimethylhex-3-ene.
My issue is with the 1-methyl part. Isn't this compound just the same as 2,4-dimethylhept-3-ene?
|
Can x = 1 for a compound of the form x-methyl-3-hexene? |
I came across a question in a textbook *Chemistry Live* by Declan Kennedy:
> Draw the structural formula for the compound 1,3,5-trimethylhex-3-ene.
My issue is with the 1-methyl part. Isn't this compound just the same as 2,4-dimethylhept-3-ene?
I don't think it is a typo as it appears again in an updated versi... |
How long burned tobacco/cigarette smoke remain toxic? |
> In the following sequence of reactions:
>
> $$\ce{CH3-CH2-CH2-I ->[\text{Alc.}~KOH] \textbf{A} ->[Br2] \textbf{B} ->[NaNH2/NH3] \textbf{C}}$$
>
> the product **C** is:
>
> 1. alkene
> 2. alkanol
> 3. alkyne
> 4. alkylamine
I haven't really came across a reagent $\ce{NaNH2}/\ce{NH3}$ in my whole se... |
I've studied $\mathrm{p}K_\mathrm{a}(\ce{H2O}) = 15,$ and anything with a $\mathrm{p}K_\mathrm{a}$ lower than should be an acid. Guanidine has a $\mathrm{p}K_\mathrm{a}$ of $13.8$ and is being called by [Wikipedia](https://en.wikipedia.org/wiki/Guanidine) a strong base. Why is it so?
According to [Wikipedia](https:/... |
Why is guanidine considered a strong base? |
Which one of the following is NOT a haloalkane? |
A) Freon
B) Teflon
C) Iodoform
D) Vinyl chloride
Well every compound here seems to me as a haloalkane, freon (no doubt) ,teflon (nah !!!) ,iodoform (never ever in a million years!), vinyl chloride (h*** no!)
Ps- My text says it is vinyl chloride, but how ? |
A) Freon
B) Teflon
C) Iodoform
D) Vinyl chloride
Well every compound here seems to me as a haloalkane: freon, teflon, iodoform, and vinyl chloride (h*** no!)
PS My text says it is vinyl chloride, but how ? |
I am planning a reaction in which I iodate phthalic anhydride. My reaction is I2, phthalic anhydride, and copper(II) chloride as a catalyst. The solvent is 99.9% isopropanol. How do I separate the product (4-Iodophthalic anhydride) from the copper(II) chloride and remaining iodine?
Edit: I planned to boil away the s... |
How to separate copper(II) chloride from 4-iodophthalic anhydride? |
A) Freon
B) Teflon
C) Iodoform
D) Vinyl chloride
Well every compound here seems to me as a haloalkane: freon, teflon, iodoform, and vinyl chloride
PS My text says it is vinyl chloride, but how ? |
Interesting question but keep in mind that it is normal to dislike a subject. You don't *have to* like chemistry. Many people loathe physics and mathematics. The world is not affected. I am sure your experience is limited to general chemistry and Oxtoby. In statistical terms, one cannot and should not trust a single sa... |
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