Atmospheric Chemistry Challenge

What is the definition of a pure substance?

• A pure substance is always a gas at room temperature.

• A pure substance is a material with a constant composition and consistent properties, either an element or a compound.

• A pure substance can have varying properties depending on its environment.

• A pure substance is a mixture of different elements and compounds.

Which technique is used to separate mixtures based on their different solubilities?

• Centrifugation

• Filtration

• Chromatography

• Distillation

Fill in the blank: A __________ is a mixture with a fixed composition that has specific properties.

• solution

• compound

• element

• substance

What gas is produced when a candle burns?

• Carbon dioxide

• Hydrogen

• Nitrogen

• Oxygen

Identify the gas: It is colourless, odourless, and is produced during respiration. What is it?

• oxygen

• carbon dioxide

• nitrogen

• hydrogen

What are the main gases that made up the early Earth's atmosphere?

• Oxygen, hydrogen, sulfur dioxide

• Carbon monoxide, argon, ozone

• Water vapor, carbon dioxide, nitrogen, methane, ammonia

• Nitrous oxide, helium, xenon

Explain how carbon dioxide contributes to the greenhouse effect.

• Carbon dioxide cools the atmosphere by reflecting sunlight.

• Carbon dioxide is a solid that forms clouds in the atmosphere.

• Carbon dioxide contributes to the greenhouse effect by trapping heat in the atmosphere, preventing it from escaping into space.

• Carbon dioxide has no impact on the greenhouse effect.

What is the primary source of methane emissions?

• Landfill operations and waste decomposition.

• Industrial waste management practices.

• Agriculture, especially livestock and manure management.

• Natural gas extraction and processing.

List two causes of atmospheric pollution.

• Natural disasters

• Household waste

• Vehicle emissions, industrial discharges

• Agricultural runoff

What is the chemical formula for methane?

• CH4

• C2H6

• CO2

• CH3OH