Which of these statements is not true about the chemical reaction rates

a. the reaction rates can change
b. the reaction rates can increase
c. the reaction rates can decrease
d. the reaction rates are always constant

D is the correct answer. Chemical reaction rates won't always be constant, you can change the rate of a chemical reaction. Factors that affect chemical reaction rates would be temperature, the concentration (pressure) of the reactant, or just the general surface area (crushing a reactant would be an example). Solvent polarity can also decrease the rate of a chemical reaction. Therefore, A, B, and C are true, leaving D as the answer.

Here Is Your Answer

D. the reaction rates are always constant.

REASON: No chemical reaction is a perfect one. Every time slight variation can be seen in the chemical reactions.

So, reaction rates are not always constant.

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most historians agree that gabriel mouton, the vicar of st. paul’s church in lyons, france, is the “founding father” of the metric system. he proposed a decimal system of measurement in 1670. mouton based it on the length of one minute of arc of a great circle of the earth (now called a nautical mile, 1852 meters). he also proposed the swing-length of a pendulum with a frequency of one beat per second as the unit of length (about 25 cm). a pendulum beating with this length would have been fairly easy to produce, thus facilitating the widespread distribution of uniform standards. over the years, his work was revised, improved, and extended by a number of french scientists.

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