The quantity of energy released or absorbed as heat during a chemical reaction is called the 28. a. temperature. c. entropy d. free energy enthalpy of reaction.

enthalpy of reaction.

Explanation:

Temperature of the gas is defined as the degree of hotness or coldness of a body. It is expressed in units like and

Entropy is the measure of randomness or disorder of a system. If a system moves from  an ordered arrangement to a disordered arrangement, the entropy is said to decrease and vice versa.

Free energy is the amount of energy that can be converted into useful work.

Enthalpy of the reaction is the difference between the energy of products and the energy of reactants. it is either the heat released or absorbed during the reaction. It is either positive or negative.

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e

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