Answer to Question #302162 in General Chemistry for Cherry

Question

Express the quantity in the unit indicated and designate whether this heat is gained or lost by the substance.

a. The quantity of heat in calories when 162.5 grams of water undergoes a temperature decrease from 45.84 degrees Celsius to 40 degrees Celsius

b. The quantity of heat in Kilojoules when 43.5 Kg of chloroform, CHCl3 has its temperature changed from 16.8 degrees Celsius to 22.3 degrees Celsius (specific heat of CHCl3 = 0.971KJ/kg-degrees Celsius

Answer 1

a) specific heat capacity of water

$=1 \>cal.^°c^{-1}.g^{-1}$

H$=162.5×1×(45.84-40)$

$=949\>calories$

The heat is lost

b)$H=43.5×0.971×(22.3-16.8)\\=232.3kJ$

The heat is gained