Abeka Science Gr. 8/ Quiz#15

About how much of the earth's surface is covered with water?

• 10%
• 50%
• 70%

• 25%

What causes the ocean to be blue?

• The depth of the ocean
• The reflection of the sky
• water's natural color

• The presence of blue algae

A chemist is studying the composition of a sample of ocean water. He gently heats the sample to evaporate the water, leaving him with the solid substances that had been dissolved in the sample. Next, he performs a series of procedures to separate the solid substances from each other. Finally, he measures how much of each solid he has obtained. What substance would he probably have the most of?

• Sodium chloride

• Calcium acetate

• Magnesium sulfate

• Potassium Nitrate

What is a huge chunk of floating glacial ice?

• Iceberg
• Ice cap

• Ice shelf

• Sea ice

What is the outermost edge of a glacier floating on the ocean?

• Ice cap

• Iceberg
• Glacial retreat
• Ice shelf

Two main factors that affect the density of seawater are ___ and ___

• temperature and salinity
• pressure and depth
• wind and currents
• oxygen and pH

The amount of dissolved solids in seawater is seawater's ___

• density
• viscosity
• pH level
• salinity

The metric unit scientists usually use to measure ocean water pressure is __

• KIlopascal

• inches
• kilograms
• miles

Study of Earth's oceans

• Oceanography
• Astronomy
• Botany
• Meteorology

The underwater boundary where cold, deep water meets sun-warmed surface water is the ___

• Equator
• Stratosphere
• Troposphere
• Thermocline