Classify the processes as endothermic or exothermic.

Question

Classify the following:

Baking a cake

ice melting

the chemical reaction inside an instant cold pack

water condensing on a surface

a car using gasoline

Answer 1

Endothermic = heat is absorbed by the system, or heat is added to the system

Exothermic = heat is released from the system to the surroundings

Baking a cake: heat is added to the system, so this is endothermic

Melting ice: heat is added to the system, so this is endothermic

Chemical reaction inside cold pack: the cold pack is getting cold, so heat is being added to the system, or looking at it another way, heat is being absorbed from the surroundings. This is endothermic

Water condensing: water is going from a gas to a liquid, so heat is being removed or released from the system, and this is exothermic

A car using gasoline: there is a combustion reaction of the gasoline which generates heat, so this is exothermic