Edexcel GCSE Chemistry C1 Topic 1 Higher

Josh Newton

Unit 1 - topic 1 - early atmosphere

The early atmosphere was formed by volcanoes.It contained large amounts of Carbon Dioxide and Water vapour

Very small amounts of Oxygen and other gasesThe Earth was very hot to start off with, and there were no oceans.

As the Earth cooled, the water vapour in the atmosphere condensed to form liquid water. This became the oceans.

Questions

Q - Why is it difficult to be precise about the early atmosphere? (E-C)

Q - Write the balanced equation for the formation of Iron Oxide Fe(2)O(3). Give the state symbols (A*-B)

Answers

A - Because people weren’t around at the time to measure it

A - 4Fe (s) + 3O(2) (g) → 2Fe(2)O(3) (s)

A changing atmosphereThe atmosphere is shown in thepie chartThe atmosphere also contains water vapour but this is not included because it

changes depending on the weatherThe atmosphere is changed by human activities such as:

● Burning fossil fuels releases Carbon dioxide into the atmosphere. Burning coal also releases Sulfur dioxide

● Farming as cattle and rice crops release methane● Deforestation adds carbon dioxide to the atmosphere if the trees are burnt.

There are also fewer trees to photosynthesize and remove carbon dioxide in the atmosphere

● There are also natural causes such as volcanos emitting carbon dioxide and sulfur

Questions

Q - Explain how the following activities can change the atmosphere:

● Deforestation● Generating electricity using fossil fuels

Answers

A - 1. Less trees to photosynthesize so less carbon dioxide is removed

2. Burning fossil fuels emits carbon dioxide - and if it is coal then sulfur dioxide.