Question

When water boils, what happens? a. The hydrogen atoms break away from the oxygen and escape as vapor. b. Hydrogen bonds are broken between neighboring water molecules. c. The bond between one water molecule and another becomes stronger. d. Covalent bonds are broken between oxygen and hydrogen atoms. e. Ionic bonds are broken when the minerals in water are heated.

Answer 1

b. Hydrogen bonds are broken between neighboring water molecules.

Step-by-step explanation:

When water reaches its boiling point, it undergoes a phase transition from liquid to gas. At this stage:

b. Hydrogen bonds are broken between neighboring water molecules:

Water molecules are held together by hydrogen bonds, weaker attractions between the positively charged hydrogen atoms of one molecule and the negatively charged oxygen atoms of adjacent molecules.

Heating disrupts these hydrogen bonds, allowing the water molecules to overcome the intermolecular forces holding them together as a liquid. As a result, the molecules transition from a liquid phase to a gaseous phase, forming water vapor.

The other options do not accurately represent what happens when water reaches its boiling point:

Answer 2

The correct answer to the question is:

b. Hydrogen bonds are broken between neighboring water molecules.

When water boils, the physical state of water changes from liquid to gas (vapor). This process is known as vaporization, which includes both evaporation and boiling. Here's a step-wise explanation of what occurs at the molecular level:

1. Increase in Energy: As water is heated, the energy of the water molecules increases.

2. Disruption of Hydrogen Bonds: Water molecules are held together by hydrogen bonds, which are weaker than covalent bonds. These are the bonds between the hydrogen of one water molecule and the oxygen of a neighboring water molecule.

3.Formation of Vapor: As the temperature reaches the boiling point, the energy provided is sufficient to overcome these hydrogen bonds. The water molecules move rapidly and eventually have enough energy to break free from the liquid and form vapor.

4.Escape as Vapor: The molecules that break free from the liquid surface escape as water vapor.

Now, let's examine the given options in the context of this explanation:

a. The hydrogen atoms break away from the oxygen and escape as vapor:

This is incorrect because during boiling, the hydrogen atoms remain bonded to the oxygen atom within individual water molecules.

b. Hydrogen bonds are broken between neighboring water molecules:

This is the correct answer. Hydrogen bonds between the water molecules are broken, allowing the molecules to escape as vapor.

c. The bond between one water molecule and another becomes stronger:

This is incorrect. As water boils, the bonds between water molecules (hydrogen bonds) are broken, not strengthened.

d. Covalent bonds are broken between oxygen and hydrogen atoms:

This is incorrect. The covalent bonds within water molecules remain intact during boiling. If these bonds were broken, it would result in the formation of hydrogen gas and oxygen gas, not water vapor.

e. Ionic bonds are broken when the minerals in water are heated:

This is incorrect. Boiling water does not break ionic bonds of dissolved minerals. The boiling process only affects the hydrogen bonds between water molecules.