Properties of Water: Structure and Phases of Matter

1.  Which of the following statements best describes a water molecule?

• Water has an overall positive charge
• Water has an overall negative charge
• The uneven sharing of electrons causes a slightly positive and negative side.
• The even sharing of electrons.

What percentage of the Earth's water is salt water?

• 3%
• 10%
• 70%
• 97%

When gas changes into a liquid, it is called...

• Melting
• Evaporation
• Condensation
• Sublimation

True or False:  Water sinks when it freezes.

• True
• False

Why is water called the universal solvent?

• It dissolves many substances.
• It is non-polar.
• Because of the water molecule's two oxygen atoms.
• Because of hydrogen's negative charge.

Which of the following statements best describe a polar molecule?

• It has more electrons than protons.
• It has an overall positive charge
• It has a positive side and negative side
• It has an overall negative charge

What is an example of condensation?

• Rain falling from the sky
• Hair drying after swimming
• Ice becoming a gas, such as dry ice
• A person exhaling on a cold window

The oxygen atom in a molecule of water has what kind of charge?

• Positive
• Negative
• Both positive and negative
• No charge

The hydrogen atoms in a molecule of water has what kind of charge?

• Positive
• Negative
• Both positive and negative
• No charge

Which of the following is not a state of matter?

• Solid
• Liquid
• Gas
• Element