A0.5865-g sample of lactic acid (hc3h5o3) is burned in a calorimeter whose heat capacity is 4.812 kj/oc. the temperature increases from 23.10 °c to 24.95 °c. calculate the heat of combustion of lactic acid (a) per gram and (b) per mole.

a) 15.2 kJ/g

b) 1367 kJ/mol

Explanation:

Given:

Mass of lactic acid = 0.5865 g

Heat capacity C of calorimeter = 4.812 kJ/C

Initial temperature, T1 = 23.10 C

Final temperature, T2 = 24.95 C

To determine:

Heat of combustion/gram and heat/mole lactic acid

Calculation:

Molar mass of lactic acid = 90.08 g/mol

The heat of combustion is given as:

where C = heat capacity of calorimeter

T1 and T2 are the initial and final temperatures

a) heat of combustion per gram

b) heat of combustion per mole

answer; natural resources;