A Substance Has a Melting Point of 20°C and a Heat

question 63

Multiple Choice

A substance has a melting point of 20°C and a heat of fusion of 3.4 × $10^4$ J/kg.The boiling point is $150 ^ { \circ } \mathrm { C }$ and the heat of vaporization is $6.8 \times 10^4 \mathrm {~J} / \mathrm { kg }$ at a pressure of one atmosphere.The specific heats for the solid,liquid,and gaseous phases are 600 J/kg ∙ K (solid) ,1000 J/kg ∙ K (liquid) ,and 400 J/kg ∙ K (gaseous) .How much thermal energy is required to raise the temperature of $1.90 \mathrm {~kg}$ this substance from $- 4 ^ { \circ } \mathrm { C }$ to $106 ^ { \circ } \mathrm { C }$ at a pressure of one atmosphere?

• A)260 kJ
• B)190 kJ
• C)230 kJ
• D)92 kJ
• E)320 kJ

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Definitions:

Crepuscular

Describing organisms that are most active during the twilight periods at dawn and dusk.

Circadian Rhythm

Circadian rhythm refers to the natural, internal process that regulates the sleep-wake cycle and repeats roughly every 24 hours.

Long-Term Change

A significant modification or transformation that occurs over an extended period, impacting environments, societies, or biological evolution.

Learning

The process by which knowledge or skills are acquired as a result of experience; a change in the behavior of an animal that results from experience.