Round the measurement to 3 significant figures. 13.06

13.1

Explanation: just round the .06 to 1 creating three sig figs.

When this reaction occurs, strong ionic bonds form between two oppositely charged particles (ions). Magnesium is a group II metal, and therefore has two electrons in it's highest energy level (or outermost electron shell). ... Therefore, they readily take up these two electrons to form negatively charged O2- ions