Question

what is the formula for calcium oxide?
cao2
ca2o
cao
ca2o2
none are correct
question 4 (1 point)
what is the correct name for mgcl2?
magnesium ii chloride
magnesium dichloride
magnesium chloride ii
dimagnesium chloride
magnesium chloride

Explanation:

Calcium has a +2 oxidation state and oxygen has a -2 oxidation state. In calcium oxide, the charges balance in a 1:1 ratio, giving the formula CaO. For MgCl₂, magnesium is a Group - 2 element with a +2 oxidation state and chlorine is a halogen with a -1 oxidation state. In naming ionic compounds with main - group metals like magnesium, we don't use Roman numerals or prefixes like "di -" for the metal or non - metal in simple binary ionic compounds. The name is magnesium chloride.

Answer:

1. C. CaO
2. E. Magnesium Chloride