What percentage of Earth's surface is covered by water?

More than 70%

Which of the following is the chemical formula for water? A) H₂O B) O₂H C) H₂O₂ D) HO

A) H₂O

Riddle: I exist in three states, clear as can be, essential for life, what am I?

Water

True or False: Water boils at 100°C at all altitudes.

False. Water boils at a lower temperature at higher altitudes due to lower pressure.

Water expands on freezing, resulting in ice having a relative density of ______.

0.92

The property of water that allows marine life to survive under ice is known as ______.

Anomalous expansion of water

Which property of water requires 2268 J/g to convert it to steam at 100°C?

Latent heat of vaporization

Fill in the blank: A solution is a uniform mixture of solute and ______.

Solvent

True or False: Hard water readily forms lather with soap.

False. Hard water does not easily form lather with soap.

What is the term for the process where hydrated crystals lose water to dry air?

Efflorescence

Which of the following is a characteristic of a true solution? A) Uniform mixture B) Can be separated by filtration C) Particles scatter light D) Particles settle

A) Uniform mixture

Fill in the blank: The maximum density of water occurs at ______ degrees Celsius.

4

Which type of water contains dissolved minerals like bicarbonates, sulfates, or chlorides of calcium and magnesium?

Hard water

What type of solution contains only calcium and magnesium bicarbonates and can be softened by boiling?

Temporary hard water

True or False: The solubility of most solids in water decreases with an increase in temperature.

False. The solubility of most solids increases with temperature.

What is the term for substances that absorb moisture from the air and dissolve into a solution?

Deliquescent substances

Fill in the blank: The phenomenon of a saturated solution losing solute when cooled is called ______.

Crystallization

The process of removing temporary hardness from water by boiling expels ______.

CO₂