Concept explainers
(a)
Interpretation:
The reason for using ethyl chloride (a spray that evaporates quickly) during a game to numb a sports injury should be explained.
Concept Introduction: Evaporation is the process of converting water (mostly) in liquid state to the gaseous state. Due to change in state of water from liquid to gas its temperature increases and energy is required for such change in state, Thus the water molecules undergoing evaporation, decreases the temperature of the surface by absorbing the heat energy from it.
(b)
Interpretation:
The reason for the faster evaporation of water in a flat dish than in the narrow vase should be determined.
Concept Introduction:
Evaporation is the process of converting water (mostly) in liquid state to the gaseous state. Due to change in state of water from liquid to gas its temperature increases and energy is required for such change in state, Thus the water molecules undergoing evaporation, decreases the temperature of the surface by absorbing the heat energy from it.
(c)
Interpretation:
The reason for the drying of sandwich that is placed on a plate as compared to the one placed in the plastic wrap should be determined.
Concept Introduction: Evaporation is the process of converting water (mostly) in liquid state to the gaseous state. Due to change in state of water from liquid to gas its temperature increases and energy is required for such change in state, Thus the water molecules undergoing evaporation, decreases the temperature of the surface by absorbing the heat energy from it. The process of evaporation increases on increasing the temperature.
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EP BASIC CHEMISTRY-STANDALONE ACCESS
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