## Chemistry Lab C

Jacobi
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### Re: Chemistry Lab C

Dinoswarleafs wrote:
Jacobi wrote:
```Volume of Object = 12.0 mL
Density = m/V = 8.7 g/mL = 8700 kg/m^3```

Give an element for n-type doping w/ Silicon
`Arsenic?`

Dinoswarleafs
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### Re: Chemistry Lab C

Jacobi wrote: Usually, the person who answered correctly asks the next question.
Oops sorry. Havent done this before D:

Jacobi
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### Re: Chemistry Lab C

What is the pH of a mixture of $10^{-4}$ molar ammonium with $10^{-7}$ molar ammonia in aqueous sol'n? Ammonium has a $pK_a$ of 9.20.

Dinoswarleafs
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### Re: Chemistry Lab C

Jacobi wrote:What is the pH of a mixture of $10^{-4}$ molar ammonium with $10^{-7}$ molar ammonia in aqueous sol'n? Ammonium has a $pK_a$ of 9.20.
`[img]https://cdn.discordapp.com/attachments/294282012146139147/506294811070824468/20181028_213345.jpg[/img]`
You made me realize on the UT inv yesterday I put the formula for ammonia as a base instead of ammonium dissociating. I was one off from placing. AAAAAAAAAAAAAAAAAAAAAAAAA

Jacobi
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### Re: Chemistry Lab C

Dinoswarleafs wrote:
Jacobi wrote:What is the pH of a mixture of $10^{-4}$ molar ammonium with $10^{-7}$ molar ammonia in aqueous sol'n? Ammonium has a $pK_a$ of 9.20.
`[img]https://cdn.discordapp.com/attachments/294282012146139147/506294811070824468/20181028_213345.jpg[/img]`
You made me realize on the UT inv yesterday I put the formula for ammonia as a base instead of ammonium dissociating. I was one off from placing. AAAAAAAAAAAAAAAAAAAAAAAAA
The image didn't load for me.

greenmilktea
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### Re: Chemistry Lab C

Jacobi wrote:What is the pH of a mixture of $10^{-4}$ molar ammonium with $10^{-7}$ molar ammonia in aqueous sol'n? Ammonium has a $pK_a$ of 9.20.
`6.2`
A solution of a diprotic acid is standardized by titration with 0.20M NaOH. Calculate the molarity of the acidic solution if 30.24mL of the NaOH solution is required to completely neutralize 14.25mL of the acid solution.

Jacobi
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### Re: Chemistry Lab C

greenmilktea wrote:
Jacobi wrote:What is the pH of a mixture of $10^{-4}$ molar ammonium with $10^{-7}$ molar ammonia in aqueous sol'n? Ammonium has a $pK_a$ of 9.20.
`6.2`
A solution of a diprotic acid is standardized by titration with 0.20M NaOH. Calculate the molarity of the acidic solution if 30.24mL of the NaOH solution is required to completely neutralize 14.25mL of the acid solution.
`.212M`
List two laws (i.e. Maxwell's Laws, Lorentz Law) involving magnetism and explain what they imply.

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### Re: Chemistry Lab C

I guess I will bump with a question.
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primitivepolonium
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### Re: Chemistry Lab C

whythelongface wrote:I guess I will bump with a question.
No one's answered, so I'll go--HI.

Rule of strengths: ARIO (atom holding the charge, resonance, inductive effects, orbital), in that order. Usually you only get to A with mineral acids, since the proton is often attached to different Hs.

Since F, Cl, Br, I are all in the same family, electronegativity is not the main factor. What matters is bond dissociation energy. The H-I bond is easier to break, so deprotonation is easier.

Also--the strength of an acid depends on the stability of its conjugate base. I- is the most stable since it's the largest. They all have a -1 charge. I- is the largest, so the negative charge is distributed over a larger space and leads to greater stability.
My turn: HCl and HBr have the same acid strength in water, but they are clearly not the same strength. (They have different pKas). Why is this the case?
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### Re: Chemistry Lab C

primitive_polonium wrote:
whythelongface wrote:I guess I will bump with a question.
No one's answered, so I'll go--HI.

Rule of strengths: ARIO (atom holding the charge, resonance, inductive effects, orbital), in that order. Usually you only get to A with mineral acids, since the proton is often attached to different Hs.

Since F, Cl, Br, I are all in the same family, electronegativity is not the main factor. What matters is bond dissociation energy. The H-I bond is easier to break, so deprotonation is easier.

Also--the strength of an acid depends on the stability of its conjugate base. I- is the most stable since it's the largest. They all have a -1 charge. I- is the largest, so the negative charge is distributed over a larger space and leads to greater stability.
My turn: HCl and HBr have the same acid strength in water, but they are clearly not the same strength. (They have different pKas). Why is this the case?
This is due to the leveling effect. In water, all the acid's strengths are leveled to H3O+, and since both completely dissociates, their strengths are leveled to that of hydronium ion. To see the difference in strength, one can use different solvent such as ammonia
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