Greenhouse Gases Flashcards

All 7 cards in this deck

What is the approximate composition of today's atmosphere?

About 80% (78%) nitrogen, about 20% (21%) oxygen, small amounts of argon, carbon dioxide (about 0.04%) and water vapour.

Name three greenhouse gases in the atmosphere.

Carbon dioxide, methane and water vapour.

What is the greenhouse effect?

Gases in the atmosphere absorb heat radiated from the Earth and re-radiate energy back, keeping the Earth warm.

True or false? Greenhouse gases absorb the heat radiated from the Earth's surface.

True. They then re-radiate energy back towards the Earth, keeping it warm.

What are the steps to find the percentage of oxygen in air using copper (or iron wool)?
e.g. 50 cm$^3$ of dry air is passed over heated copper and 40 cm$^3$ remains

1. Pass the air over the metal until no further change: oxygen is used up.
2. Find the volume used: $50 - 40 = 10$ cm$^3$.
3. Percentage $= \frac{10}{50}\times100 = 20\%$.

In the iron wool experiment on the percentage of oxygen in air, why does the water level rise in the tube?

Oxygen in the trapped air reacts with the iron, so the volume of gas decreases.

True or false? Nitrogen is the main greenhouse gas in the atmosphere.

False. Nitrogen is the most abundant gas but it is not a greenhouse gas; carbon dioxide, methane and water vapour are.