Concept explainers
(a)
Interpretation:
Whether heat is absorbed or released during melting of 100 g of ice needs to be determined.
Concept Introduction:
When in a
(b)
Interpretation:
Whether heat is absorbed or released during freezing of 25g of water needs to be determined.
Concept Introduction:
When in a chemical reaction, energy is required to form products from reactants, the reaction is known as endothermic and if energy is released, it is known as an exothermic reaction.
(c)
Interpretation:
Whether heat is absorbed or released during condensation of 20 g steam needs to be determined.
Concept Introduction:
When in a chemical reaction, energy is required to form products from reactants, the reaction is known as endothermic and if energy is released, it is known as an exothermic reaction.
(d)
Interpretation:
Whether heat is absorbed or released during vaporizing 30 g water needs to be determined.
Concept Introduction:
When in a chemical reaction, energy is required to form products from reactants, the reaction is known as endothermic and if energy is released, it is known as an exothermic reaction.
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General, Organic, & Biological Chemistry
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- Suppose a student heated the hydrate sample for approximately five seconds instead of one minute. What would be the result of not heating the sample long enough? The solid sample will completely decompose into water and anhydrate. Water may still remain in the solid sample. There might be insufficient heat to form the hydrate. The volume of the hydrate sample will increase.arrow_forwardWhen 50 g of ethanol is heated from T1 below its freezing point to a temperature T2 above its freezing point, it absorbs 523 kJ of heat. If the same sample is cooled back from T2 until it freezes and is cooled back to T1, which of the following is true? a. The sample releases more than 523 kJ of heat to its surroundings. b. The sample releases less than 523 kJ of heat to its surroundings. c. The sample releases 523 kJ to its surroundings. d. It is impossible to know without the heat of fusion of ethanol.arrow_forwardWhat is true about the specific heat of ice and water? * the same since they are essentially made up of same molecules. water has twice the specific heat of ice. ice has higher specific heat because it is colder. It depends on the initial temperature of ice. none of the above.arrow_forward
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