Question

Indicate whether each of the following statements is true or false. In a coal-fired power plant, chemical energy is first converted to thermal energy. In a coal-fired power plant, approximately 2/5 of original energy in the coal is lost to heat. The molecules in cold air move faster than in hot air.

Answer 1

Answer:

1. In a coal-fired power plant, chemical energy is first converted to thermal energy. TRUE.

The chemical energy in the coal is converted to thermal energy when the coal is burnt to produce steam.

2. In a coal-fired power plant, approximately 2/5 of original energy in the coal is lost to heat. FALSE.

Approximately 3/5 of the original energy is lost not 2/5 so this statement is false.

3. The molecules in cold air move faster than in hot air. FALSE.

Molecules with more heat move faster than molecules with less. Molecules in cold air therefore, will move slower than molecules in hot air.