4. Which of these choices best describes what a ratio shows?
A. a comparison between two quantities
B. family relationships over several generations
C. the alleles of parents and offspring for a
given trait
D. the likelihood or chance that something will
happen

a non redox reaction occurs when there is not a transfer of electrons. for redox reactions, which are reduction-oxidation reactions, a change in the oxidation number occurs. elements that are reduced gain electrons, and elements that are oxidized lose electrons.

explanation:

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.