Earth, Weather, the Water Cycle and Natural Resources
This domain tests Earth's structure and rocks, soil, weather measurement, the water cycle, and the difference between renewable and non-renewable resources.
Earth, rocks and soil
Earth has a crust, mantle, outer core and inner core. Igneous rock forms when magma cools (granite); sedimentary rock forms in layers and may contain fossils (sandstone, limestone); metamorphic rock is changed by heat and pressure (marble). Soil has topsoil rich in humus, then subsoil, then bedrock. Weathering breaks rock down; erosion moves the fragments away.
Weather and the water cycle
Weather is the day-to-day state of the atmosphere; climate is the long-term average. A rain gauge measures rainfall in millimetres, a thermometer measures temperature in °C, an anemometer measures wind speed and a wind vane shows wind direction. In the water cycle, water evaporates from seas and lakes and transpires from leaves, rises and cools, condenses into cloud droplets, falls as precipitation, then collects as runoff or soaks in by infiltration.
Natural resources
Renewable resources are replaced naturally, such as sunlight, wind, flowing water and wood. Non-renewable resources - coal, oil, natural gas and minerals - form over millions of years and will run out; burning fossil fuels adds carbon dioxide to the atmosphere.
Worked example
A puddle on a pavement disappears on a warm, breezy day. The water has evaporated: it gained energy, became water vapour and rose into the air; on a cold surface it would condense again. It did not soak through the pavement.
Traps that cost marks
Evaporation happens below boiling point. Steam is liquid droplets, not invisible water vapour. Clouds are tiny droplets, not gas.