Which of the following statements correctly describes energy levels? a. electrons can never move to a higher or lower energy level. b. the second energy level holds a maximum of four electrons. c. the greater the energy of the level, the farther away it is from the nucleus. d. in its outermost energy level, oxygen has 4 valence electrons.

C. The greater the energy of the level, the farther away it is from the nucleus.

Explanation:

A is wrong because electrons can either move to higher energy levels (if they gain energy) or to lower energy levels (if they lose energy).

B is wrong because the second energy level holds a maximum of six electrons.

C is the right choice because as we move away from the nucleus, the greater the energy of the level.

D is wrong because in its outermost energy level, oxygen has 6 valence electrons. Oxygen has 8 electrons, its distribution is: 2, 6.

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.