Which of the following are oxidation half-reactions?

cr2o72- → cr3+

mno4- → mno2

fe2+ → fe3+

cl- → cl2

Of the groups of elements below, which are most likely to gain electrons to become anions? a. alkali metal b. boron group c. halogen d. transition metal

In the 1800s, one of the statements in john dalton's atomic theory was that atoms are indivisible. later experimental evidence led to the discovery of subatomic particles such as neutrons, electrons, and protons. what happened to the indivisible atom part of dalton's atomic theory, and why?

What effect might melting sea ice have for people who live in coastal areas?