Potassium hydroxide (KOH) has a lattice energy of – 789.0 kJ/mol and a heat of hydration of -846.6 kJ/mol. What volume of solution could be heated from 25.0°C to 100.0 °C by the heat evolved from the dissolution of 25.7 g of KOH? Assume the
solution has a specific heat capacity of 4.00 and a density of 1.05 g/mL.

a. the law of proportion states the combination of 2 atoms in a specific ratio to produce multiple compounds such as the given statement of question ‘1st compound contains 88.8 % cu ’ indicates 88.8 g of cu is present along with 11.2 g oxygen in 100 g of compound whereas the statement ‘2st compound contains 79.9 % cu ’ indicates 79.9 g of cu is present along with 20.1 g oxygen in 100 g of compound

1st compound contains 88.8 g cu

for cu

m = 63 g /mol

atomic % = 88.8 /63 = 1.42

for o

m = 16 g /mol

atomic % = 11.2 /16 = 0.7

b. the emperical formula of 1st compound is

cu1.4o0.7

cu2o