Who gen chem questions (on acid-base) and on calculations

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bigbutrealdreams

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For acid-base attached, I completely do not understand the reasoning. Yes, I know the base and acid involved are strong, but the abundance part is confusing.

For calculations, I do not understand the set-up. Will I ever have to do a similar set-up on actual DAT?

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I dont fully understand the first one either.

But for the second one:

assuming a 100ml solution 70% of it is HNO3. so 70ml HNO3 for 100ml solution. Molarity is Moles per Liter solution. We can use dimensional analysis!

(70ml HNO3 / 100 ml solution) (1000 ml solution / 1 l solution ) ( 1.42 g HNO3 / 1 ml HNO3 ) (1 mol HNO3 / 63 g HNO3) Cancel all the units and leave all the numbers and its Molarity. Its easier to see written out as actual fractions..

I have seen something like the 2nd question on DBC and kaplan.
 
I dont fully understand the first one either.

But for the second one:

assuming a 100ml solution 70% of it is HNO3. so 70ml HNO3 for 100ml solution. Molarity is Moles per Liter solution. We can use dimensional analysis!

(70ml HNO3 / 100 ml solution) (1000 ml solution / 1 l solution ) ( 1.42 g HNO3 / 1 ml HNO3 ) (1 mol HNO3 / 63 g HNO3) Cancel all the units and leave all the numbers and its Molarity. Its easier to see written out as actual fractions..

I have seen something like the 2nd question on DBC and kaplan.
awesome! thanks man
 
For the first one, try to think of abundance as which side is more favored. Reactants or products?

So you have a strong organic acid and a strong organic base. They react to form ethane and t-butoxide. Even though t-butoxide is a very strong base, ethane is a terrible acid, so it will not donate that H+.
Thus the reaction will be forced to the right, that's why you have your products are in higher "abundance" once the reaction takes its course.

Hope this helps.
 
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