Which of the following statements is true? . a) chemical reaction rates vary with the conditions of the change, but nuclear decay rates do not. b) nuclear decay rates vary with the conditions of the change, but chemical reaction rates do not. c) both chemical reaction rates and nuclear decay rates vary with the conditions of the change. d) neither chemical reaction rates nor nuclear decay rates vary with the conditions of the change.

A) Chemical reaction rates vary with the conditions of the change, but nuclear decay rates do not.

Explanation:

Chemical reactions are reactions in which electrons are involved.

Nuclear reactions are reactions in which nucleus is involved.

1. Chemical reactions involve only rearrangement of electrons and nuclear changes involve changes in nuclei.

2. Different isotopes of an element behave similarly in chemical reactions but nuclear reactions are different for isotopes.

3. Rates of chemical reactions are influenced by temperature and catalysts but rates of nuclear reactions are unaffected by such factors.

4. Energy changes accompanying nuclear reactions are much larger as compared to chemical reactions.

he forelimbs below belong to four species that descended in a direct line from the ancestral mammal shown above. of the four descendants shown, which species most likely appeared earliest in evolutionary history?