Would you expect the amount of heat (q, in J) released or absorbed for the dissolution of 4 g of NH4NO3(s) in 50.0 g of water to be greater than, less than, or equal to, the amount of heat released or absorbed for the dissolution of 2 g of NH4NO3(s) in 50.0 g of water

Greater

Explanation:

This is because , 4 g of NH4NO3(s) contains more number of moles than 2 g of NH4NO3(s). Since the amount of heat (q, in J) released or absorbed for the dissolution is measured in kJ/mol, the higher the number of moles , the higher the amount of energy released. Since 4 g of NH4NO3(s) contains more number of moles than 2 g of NH4NO3(s), it will thus release or absorb more heat. So, the amount of heat is greater.

0.197 M

Explanation:

The reaction equation is:

H2SO4(aq) +2KOH(aq) > K2SO4(aq) + 2H2O(l)

number of moles of H2SO4 = 0.25 L * 0.45 M = 0.1125 moles

number of moles of KOH = 0.2 L * 0.24 M = 0.048 moles

since H2SO4 is the reactant in excess;

2 moles of KOH reacts with 1 mole of H2SO4

0.048 moles of KOH reacts with 0.048 * 1/2 = 0.024 moles of H2SO4

Amount of excess H2SO4 left unreacted = 0.1125 - 0.024 = 0.0885 moles

Total volume = 0.25 L+ 0.2 L = 0.45 L

concentration of H2SO4 = 0.0885/0.45 = 0.197 M