What is a reaction rate? PLEASE HELP a. measure of the potential energy differences in reactants and products
b. measure of the activation energy needed
c. measure of how fast products are made
d. measure of collisions between molecules

c

Explanation:

Reaction rate, in chemistry, the speed at which a chemical reaction proceeds.if you're studying the same thing I am then that would be it

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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