Question

When compounds form, which of the following statements is true about the elements that form them?

Answer 1

Answer:

C. Their properties change completely.

Explanation:

The electron configurations of the elements show a periodic variation with increasing atomic number. Consequently, there are also periodic variations in physical and chemical behavior.  

When atoms interact to form a chemical bond, they combine in order to achieve a more stable electron configuration. As a consequence, the compounds formed exhibit completely different properties.

For example, when solid magnesium burns in air, it forms both magnesium oxide and magnesium nitride, which are gases.