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Chemistry

GCSE · AQA

QuestionsFlashcards

Simple Model of the Atom
The Periodic Table
Properties of Transition Metals
- Typical Properties of Transition Metals
  7
- Transition Metals vs. Alkali Metals
  6

Ionic, Covalent & Metallic Bond
Bonding & Substance Properties
Structure & Bonding of Carbon
Bulk & Surface Properties
- Sizes of Particles & their Properties
  6
- Nanoparticles
  6

Formation of Earth's Atmosphere
CO2 & CH4 as Greenhouse Gases
Causes of Atmospheric Pollution
- Atmospheric Pollutants from Fuels
  6
- Properties & Effects of Atmospheric Pollutants
  6

Global Reserves & Potable Water
Life Cycle Analysis & Recycling
- Life Cycle Assessment
  7
- Reducing Use of Resources
  5
Using Materials
Haber Process & NPK Fertilisers

How Oxygen Increased Flashcards

All 6 cards in this deck

What is the word equation for photosynthesis?: carbon dioxide + water $\rightarrow$ glucose + oxygen
What is the balanced symbol equation for photosynthesis?: $6CO_2 + 6H_2O \rightarrow C_6H_{12}O_6 + 6O_2$
Which organisms first produced oxygen, and roughly when?: Algae, about 2.7 billion years ago.
What happened to oxygen levels in the billion years after algae evolved?: Plants evolved and the percentage of oxygen gradually increased, until it was high enough for animals to evolve.
True or false? The oxygen in the atmosphere was released by volcanoes.: False. It was produced by algae and plants by photosynthesis.
On a graph of atmospheric gases over time, carbon dioxide falls while oxygen rises at a similar rate. What process causes this?: Photosynthesis (by algae and plants).