When 2.25 g of sodium hydroxide (NaOH) was dissolved in 150.00 g of water a value of 11.00oC was obtained for ΔT.

1. Calculate the molarity of the sodium hydroxide solution.
2. Calculate the value (calories) for the heat of solution of 2.25 g of NaOH.
3. Calculate the number of calories that would be produced if one mole of sodium hydroxide was dissolved. (ΔHsolnNaOH)

2 answers

1. mols NaOH = grams/molar mass
Then M = mols/L solution. I suppose you are supposed to take the density of H2O as 1.0 g/mL which makes 150.00g H2O= 150 mL.

2. q = mass H2O x specific heat H2O x delta T

3. delta H rxn = q/2.25 give you per gram.
That x molar mass NaOH gives delta H rxn per mole.
The process for #2 didn't work. I got found the answer to be -1590 but I'm not sure how to get that answer