Carbon dioxide and global warming: the greenhouse effect

2 marks · Easy

In 1980, the average global concentration of carbon dioxide was 340 ppm (parts per million). In 2020, it increased to 415 ppm. Calculate the increase in CO2 concentration over this period.

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75 ppm (±0)

Common mistakes: Calculating percentage increase instead of difference

Show mark scheme and worked solution

Marking points

M1 · 1 mark · Correctly subtracts 340 from 415

A1 · 1 mark · Answer = 75 ppm (with correct unit)

Worked solution

Change in CO2 concentration = Final - Initial = 415 ppm - 340 ppm = 75 ppm