Question

Water (H2O) and hydrogen fluoride (HF) are both polar molecules. Which of the following statements are true about the attractions between water and hydrogen fluoride when they are mixed together?

a) The H in HF and the H in H2O attract each other.
b) The H in HF and the O in H2O attract each other.
c) The F in HF and the H in H2O attract each other.
d) The F in HF and the O in H2O attract each other.

Answer 1

The correct statements about the attractions between water (H2O) and hydrogen fluoride (HF) when mixed are that the hydrogen in HF is attracted to the oxygen in H2O and the fluorine in HF is attracted to the hydrogen in H2O, due to the formation of hydrogen bonds.

Step-by-step explanation:

When water (H2O) and hydrogen fluoride (HF) are mixed together, the attractions between these polar molecules occur due to the hydrogen bonds formed between the partially positive hydrogen atom of one molecule and the partially negative atom of another molecule. Specifically, for the statements given:

• (b) The H in HF and the O in H2O attract each other.
• (c) The F in HF and the H in H2O attract each other.

These attractions are due to the polar nature of the molecules, where HF has a highly polarized H-F bond allowing for the formation of hydrogen bonds with water. The fluorine atom in HF, being highly electronegative, will attract the partially positive hydrogen atom in water, while the hydrogen atom in HF will be attracted to the oxygen atom in water because of the lone pairs and the oxygen's partial negative charge.