The Global Carbon Cycle: Crash Course Chemistry #46

What was a key characteristic of Earth's early atmosphere?

• It contained a large amount of free oxygen.

• It was primarily composed of nitrogen and oxygen.

• It lacked free oxygen.

• It was mostly water vapor.

How do greenhouse gases affect Earth's temperature?

• They reflect heat energy back into space.

• They absorb heat energy, increasing the average temperature.

• They convert heat energy into light energy.

• They block sunlight from reaching Earth's surface.

What is the process called when plants convert carbon dioxide gas into solid organic compounds like sugars?

• Cellular Respiration

• Oxidation

• Carbon Fixation

• Photosynthesis

What are the main products of cellular respiration?

• Glucose and oxygen

• Carbon dioxide, water, and energy

• Light energy and water

• Carbohydrates and oxygen

What is formed when carbon dioxide dissolves in water?

• Oxygen gas

• Carbohydrates

• Carbonic acid

• Methane

Where is most of the Earth's carbon stored?

• In the atmosphere as carbon dioxide

• In living organisms

• As inorganic carbonates in the Earth's crust and mantle

• In fossil fuels like coal and petroleum

What is a major environmental consequence of burning fossil fuels?

• Increased oxygen levels in the atmosphere

• Reduced water vapor in the air

• Excess carbon dioxide trapping heat in the atmosphere

• Formation of new rock layers