Thermochemistry Problems

1. Dec 13, 2009

Indifference8

I have more than one problem I need help with. Any help is extremely appreciated.

1. The problem statement, all variables and given/known data

Problem 1. The heat of neutralization of HCl by NaOH is delta H of reaction = -56.2 kj/mol. How much heat is released when 125mL of 1.750 M HCl is mixed with 195mL of 0.667 M NaOH?

2. Relevant equations

q= ms delta T

3. The attempt at a solution

I have no idea how to get this problem from volume and molarity to something like grams or moles that I can actually work with.

1. The problem statement, all variables and given/known data

Problem 2. The combustion of one mole of benzene, C6H6, in oxygen liberates 3268 kJ of heat. The products of the reaction are carbon dioxide and water. How much heat is given off when 183 g of oxygen are reacted with excess benzene?

2. Relevant equations

q = ms delta T

3. The attempt at a solution

I also have no idea how to even begin this problem. I don't even quite understand what they are asking for, let alone answering it.

2. Dec 14, 2009

Staff: Mentor

Change school as fast as possible. If they have not taught you how to calculate number of moles of substance dissolved when you are given volume and concentration, they won't be able to teach you anything about termochemistry.

Basically all you need to know is that C=n/V.

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