# Problem: Identify each of the following energy exchanges as primarily heat or work and determine whether the sign of E is positive or negative for the system.a. Sweat evaporates from skin, cooling the skin. (The evaporating sweat is the system.)b. A balloon expands against an external pressure. (The contents of the balloon is the system.)c. An aqueous chemical reaction mixture is warmed with an external flame. (The reaction mixture is the system.)Identify energy exchanges as primarily heat or work.

###### FREE Expert Solution

For each of the following systems:

a. Sweat evaporates from skin, cooling the skin. (The evaporating sweat is the system.)

###### Problem Details

Identify each of the following energy exchanges as primarily heat or work and determine whether the sign of E is positive or negative for the system.
a. Sweat evaporates from skin, cooling the skin. (The evaporating sweat is the system.)
b. A balloon expands against an external pressure. (The contents of the balloon is the system.)
c. An aqueous chemical reaction mixture is warmed with an external flame. (The reaction mixture is the system.)

Identify energy exchanges as primarily heat or work.