One atom of silicon can properly be combined in a compound with
a. four atoms of calcium.
b. one atom of chlorine.
c. two atoms of oxygen.
d. three atoms of hydrogen.

C. two atoms of oxygen.

Explanation:

Step 1: Data given

Silicon has 14 electrons

Silicon is part of Group IV, all the elements there have 4 valence electrons.

It can form a compound when 4 valence electrons bind with the 4 valence elctrons of silicon

A. four atoms of calcium.

Calcium has 2 valence elctrons. 4 atoms of calcium cannot bind on 1 atom of silicon since there are only 4 valence electrons.

B. one atom of chlorine.

1 atom of chlorine has 7 valence electrons. Chlorine can bind with an atom with 1 valence electron. Since silicon has 4 valence electrons, they will not bind.

Silicon can bind with 4 atoms of chlorine to form SiCl4

C. two atoms of oxygen.

Oxygen has 6 valence electrons, this means oxygen can bind with an element with 2 valence electrons.

Since silicon has 4 valence electrons, it can bind with 2 atoms of oxygen to form SiO2 (silicon dioxide).

D. three atoms of hydrogen.

Hydrogen has 1 valence electron. 1 hydrogen atom can bind with an element that has 7 valence electrons.

Three atoms of hydrogen can bind with an element that has 5 valence electrons.

Silicon will not bind with 3 atoms of hydrogen ( but can bind with 4 atoms of hydrogen)