When 5.12 g of naoh were dissolved in 51.55 g water in a calorimeter at

24.5°c, the temperature of the solution went up to 49.8°c.

-calculate q of solution.
-find δh in kj/mol for the reaction as it occurred in the calorimeter.

Q = 6.00 kJ

given that the heat capacity of the final solution is the same as that of pure water of equal mass.

ΔH = 468 kJ/mol.

Both answers come with three sig. fig. as in data in the question.

Final mass of the solution:

.

An increase in temperature by one degree celsius is the same as an increase in temperature by one degree Kelvin. Change in temperature:

.

Assume that the specific heat capacity of the NaOH solution is the same as the specific heat capacity of pure water:

.

In other words, it takes 4.182 Joules of energy to raise the temperature of one gram of pure water by one degree Kelvin. Assume that so is the case for the NaOH solution.

Energy change:

.

Refer to a periodic table for relative atomic mass:

Formula mass of NaOH:

.

How many moles of formula units in that 5.12 gram of NaOH?

.

ΔH measures the energy change per mole of NaOH dissolved. Dissolving 5.12 grams or 0.128010 moles of NaOH releases of energy.

.

the answer is either b or c

the answer for sodium is 0.186

the answer for rubidium is 0.251