Question

multiple choice question
identify a true statement about water molecules in the vapor state.
o they are held by hydrogen bonds that constantly break and re - form.
o water molecules are held by hydrogen bonds that hold most molecules together in small groups.
o they are much closer to one another than in the liquid state.
o when water boils, nearly all the hydrogen bonds are broken, and many molecules enter the vapor state all at once.

Explanation:

In the vapor - state of water, when water boils, the heat energy overcomes the hydrogen - bonding forces. Nearly all hydrogen bonds are broken and many water molecules enter the vapor state simultaneously. In the vapor state, water molecules are not held by hydrogen bonds that constantly break and reform as in the liquid state, nor are they held in small groups by hydrogen bonds. Also, water molecules in the vapor state are much farther apart than in the liquid state.

Answer:

When water boils, nearly all the hydrogen bonds are broken, and many molecules enter the vapor state all at once.