2. Chemistry

A proton ___________:

The average oxygen atom has a mass number of 16 and an atomic number of 8. This means that the number of neutrons in this oxygen atom is:

How many valence electrons does an atom with five total electrons have?

Which of the following is true about electron energy shells?

In the term trace element, the adjective trace means that a. the element is required in very small amounts. b. the element can be used as a label to trace atoms through an organism's metabolism. c. the element is very rare on Earth. d. the element enhances health but is not essential for the organism's long-term survival.

We can be sure that a mole of table sugar and a mole of vitamin C are equal in their a. mass. b. volume. c. number of atoms. d. number of molecules.

The reactivity of an atom arises from a. the average distance of the outermost electron shell from the nucleus. b. the existence of unpaired electrons in the valence shell. c. the sum of the potential energies of all the electron shells. d. the potential energy of the valence shell.