I am doing a lab concerning pH...
Why is it necessary to allow a mixture of 25mL of a 0.1M HCl solution with 20mL of a 0.08M NaOH solution to cool to room temperature? (I don't know if the actualy concentrations matter)
Does it affect the pH?
Yes, temperature affects the pH but you don't give enough information to know if that is the answer to the question or not.
First Question:
Mix 25mL of a 0.1M HCl solution with 20mL of a 0.08M NaOH solution to and allow to cool to room temperature. Calculate the theoretical yield.
My answer: 1.70
The experiment was then performed and the observed pH was 1.5
Afterwards, it asks, "Why was it necessary to allow the mixture to cool to room temperature?"
Mixing HCl and NaOH produces NaCl and water. I presume the question is asking for theoretical yield of NaCl. It is 0.08 mols/L x 0.02 L x 58.5 (you need to get the exact value) = ?? grams and watch the sifnificant figures if your prof does. My guess, then, is that you are to collect the NaCl, weigh it, and calculate the percent yield. The reason for cooling the solution before filtering and collecting the NaCl is to decrease the solubility of the NaCl; otherwise, the percent yield will be decreased. This is a guess and I may be off base on guessing what you are doing.
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