Which of the following pairs of elements is most likely to form an ionic compound? a. nitrogen and sulfurb. sodium and aluminumc. magnesium and fluorined. oxygen and chlorine

Option c, Mg and F

Explanation:

Let's think this question.

a. Nitrogen and Sulfur. They make a covalent bond to form N2S3. They are both non metallic.

b. Na and Al, it is impossible for two metals to make a ionic compound

d. O and Cl also are joined by covalent bond to form Cl2O3. They are both non metallic.

C is the best choice. A non metallic and a metallic element usually makes a ionic compound. It can be assured by the EN (Pauling Rule). We should substract EN (data in periodic table)

ΔΕΝ = EN F - EN Mg

ΔΕΝ = 4 - 1.2 = 2.8

This is absolutely a ionic compound

If ΔΕΝ > 1.7, it is a ionic bond

If 0.4 < ΔΕΝ > 1.7 it is a polar covalent bond

If ΔΕΝ < 0.4 it is a non polar covalent bond

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.