Final answer:
The correct matches for the given terms and definitions are endothermic process for a change that absorbs energy, reaction rate for the speed at which a chemical change occurs, weight for the effect of gravity on mass, and hardness for a measure of the ability to scratch another substance. The correct option is B.
Step-by-step explanation:
To match the given terms with their definitions accurately, you need to have an understanding of basic concepts in chemistry. Here are the correct matches based on the options provided:
- a. change that absorbs energy this is known as an endothermic process, where a chemical reaction or physical change absorbs heat.
- b. speed at which a chemical change occurs this refers to the reaction rate of a chemical reaction, which is influenced by factors such as temperature, concentration, and the presence of a catalyst.
- c. effect of gravity on mass is related to weight, which is the force exerted by gravity on an object's mass.
- d. a measure of the ability to scratch another substance is a reference to hardness, often tested using the Mohs scale.
- e. change that releases energy is an exothermic process, where energy is released, typically in the form of heat, during a chemical reaction or physical change.
- f. matter with definite shape and volume describes a solid, which has a fixed shape and volume.
- g. ability to burn is known as flammability, which is a chemical property that describes how easily a substance will ignite or catch fire.
- h. substance that increases reaction rate refers to a catalyst, which speeds up a chemical reaction without being consumed by the reaction itself.
- i. mass per unit volume is the definition of density, an important physical property of substances.
- j. minimum energy required for chemical reaction is known as the activation energy, which is the lowest amount of energy needed to initiate a chemical reaction.
Given these definitions, the correct match from the options provided is Option B:
- a. change that absorbs energy -e (endothermic process)
- b. speed at which a chemical change occurs -h (reaction rate)
- c. effect of gravity on mass -i (weight)
- d. a measure of the ability to scratch another substance -g (hardness)