Quiz-a-Day Challenge (Day 6)- Grade 8

What is the process by which carbon is returned to the atmosphere in the carbon cycle?

• A. Photosynthesis
• B. Respiration
• C. Combustion
• D. Decomposition
• E. Erosion

What is the purpose of the periodic table?

• A. To organize elements based on their atomic number
• B. To organize elements based on their atomic mass
• C. To organize elements based on their color
• D. To organize elements based on their texture
• E. To organize elements based on their melting point

How do humans contribute to the carbon cycle?

• A. By burning fossil fuels
• B. By deforesting large areas
• C. By using certain industrial processes
• D. All of the above
• E. None of the above

Which of the following is a mixture?

• A. Water
• B. Oxygen
• C. Sugar
• D. Salt water
• E. Iron

Which of the following is a greenhouse gas that contributes to climate change?

• A. Carbon dioxide
• B. Oxygen
• C. Nitrogen
• D. Water vapor
• E. All of the above

Which of the following elements is a halogen?

• A. Sodium
• B. Chlorine
• C. Calcium
• D. Iron
• E. Aluminum

Which of the following best describes a solution?

• A. A mixture in which one substance is evenly distributed throughout another substance
• B. A mixture in which the substances are not evenly distributed
• C. A mixture in which two substances combine to form a new substance
• D. A mixture in which the substances can be easily separated
• E. None of the above

What is the primary source of carbon in the carbon cycle?

• A. Carbon dioxide in the atmosphere
• B. Carbon in the oceans
• C. Organic matter in soil
• D. Carbon in rocks and minerals
• E. Carbon in fossil fuels

Which of the following is an example of a carbon sink?

• A) The atmosphere
• B) The ocean
• C) A landfill
• D) A factory

What is the main cause of the increase in atmospheric carbon dioxide levels over the past century?

• A) Deforestation
• B) Volcanic activity
• C) Burning of fossil fuels
• D) Changes in ocean currents