| A | B |
|---|
| decaying plants and animals in soil | humus |
| broken up pieces of rock are formed by | weathering |
| type of soil with small particles and little room for air | clay soil |
| type of soil with large air spaces and big particles | sandy soil |
| best soil for growing plants | loam |
| pH for cabbage | 6-7.5 |
| pH for potatoes | 4.5-6 |
| added to soil which is too acidic | lime |
| freeze fracturing | physical weathering |
| acid rain | chemical weathering |
| tree roots | biological weathering |
| lightning forms | nitrogen oxides |
| reacts with substances | corrosive |
| renders harmful gases harmless in cars | catalytic converters |
| reduce acidic gas emissions from power stations | sulphur precipitators |
| only survive in very clean air | lichens |
| produced when water droplets form around smoke particles | smog |
| O3 | ozone |
| destroy the ozone layer | CFCz |
| absorbs harmful UV rays from the sun | ozone layer |
