Magnesium and chlorine atoms combine in the ratio of 1:2 to form one molecule of magnesium chloride.

The correct option is A

True

Magnesium chloride is an ionic compound in which the positively charged magnesium ions are surrounded by negatively charged chlorine ions and negatively charged chlorine ions are surrounded by positively charged magnesium ions. Magnesium and chlorine atom combines in the ratio similar to their valency. Magnesium has valency 2 and chlorine has valency 1.
Therefore, magnesium and chlorine atoms combine in the ratio of 1:2 to form 1 molecule of magnesium chloride.