Question

Calculate the amount of heat needed to melt 123. g of solid acetic acid (HCH,CO,) and bring it to a temperature of 98.1 °C. Be sure your answer has a unit symbol and the correct number of significant digits. X 5 ?

Answer 1

Meltig point of acetic acid CH COOH 16.6°C Step 1 Conversion of CHCOOH solid from 16.6°C to 16.6°C mass of CH,COOH 123 g Heat of fusi on of CH2COOH 192.09 J/g 192.09 J Amount of heat required in this process, q =123 g x- = 23627 J 23.627 kJ Step2: Conversi on of liquid CH2COOH from 16.6°C to 98.1°C Heat capcity of liquid CH2COOH, s 2.05- g.C Change in temperature,AT = 98.1°C-16.6 °C 81.5°C Amount heat required in the process 42 msAT J 123 g x 2.05 g.°C 20550 J 20.55 kJ -(81.5"c) Total amount of heat needed in the process, q = q + q -23.627 kJ 20.55 J = 44.177 kJ = 44.2 kJ = 44.2x103 J