Identify each energy exchange as primarily heat or work and determine whether the sign of δe 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.)

Question

Christopher Hardy

Chemistry

22 April, 16:46

Identify each energy exchange as primarily heat or work and determine whether the sign of δe 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.)

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Answers (1)

Know the Answer?

Ty Kirk · Answer 1

A. Heat. Positive as the sweat gains heat to evaporate.

B. Work. Negative as the balloon does work to expand.

C. Heat. Positive as heat is transferred to the mixture to warm it up.