Water Properties CiHS 2020

What two elements make up water?

• Helium and oxygen

• Hydrogen and oxygen

• helium and carbon

• oxygen and carbon

What does "polar" mean?

• A molecule is cold
• A molecule has ionic bonds
• A molecule has covalent bonds
• A molecule has areas of positive and negative charge

What word describes when water is attracted to other substances?

• cohesion
• adhesion
• capillary action
• surface tension

Attractions between the negative part of one water molecule and the positive part of another molecule are called

• Covalent bonds

• Ionic bonds

• Polar bonds

• Hydrogen bonds

Which part of a water molecule has a slightly positive charge?

• the oxygen atom

• the hydrogen atoms

• the whole molecule is slightly positive

• there are no parts with a positive charge

Surface tension is the property of water in which...

• water molecules at the surface tend to stick together.

• water spills easily.

• water tends to be see-through.

Describe COHESION.

• Water molecules attracted to other substances.

• Water molecules climbing upwards against the force of gravity.

• Water molecules dissolving many substances because of its polarity.

• Water molecules attracted to other water molecules.

Which of the following characteristics of water is not a result of hydrogen bonding?

• adhesion

• surface tension

• cohesion

• All of the above are a result of hydrogen bonding.

Small insects can walk across the surface of calm water. Their feet push the surface of the water down slightly, somewhat like a person walking across a trampoline, but they do not break the surface. What is the best explanation for why this happens?

• The insects are light enough so that they do not break the hydrogen bonds holding the water molecules together

• The insects actually use their wings to hover slightly above the water's surface and they only skim it with their feet

• The insects' feet are non-polar, so they are repelled by the polar water molecules and are pushed away from the water's surface

• The insects are small enough to see the individual water molecules, so they are able to step carefully from one molecule to the next

Capillary action is the result of adhesion. Which aspect of water is responsible for this?

• Nonpolar covalent bonds enable water to dissolve other substances.
• Polar covalent bonds join molecules of water to other substances.
• Hydrogen bonds form between water and another substance.
• Ionic bonds enable electrons to flow through water and into another substance.