28. Define the following terms: a)Independent variable The thing that is different in each set up. The variable we change. b)Dependent variable The thing we measure (results) c)Controlled variable Things we keep the same in our experiment
Independent Variable Dependent Variable Controlled Variables Soil Type (clay, loam, sand)Amount of water in beaker 40mL of water in each funnel Amount of soil in each funnel
1.Describe a resource – A resource is anything supplied by the Earth to satisfy a particular need 2.Name the six natural Earth resources minerals and fossil fuels (like coal and oil) found in rocks soil air water living things sunlight 3. Explain what is meant by a renewable resource. Give examples. A resource that is always being replaced naturally eg sunlight, water, wind 4. Explain what is meant by a non-renewable resource. Give examples. A resource that is being used at a rate greater than it is being replaced eg coal, gas, petrol Non renewable resources take more that 80 years to be replaced
Renewable Expensive to implement (build turbines) Free to run Back up energy source may be needed Space required to create Will not run out Not widely available No increase in greenhouse effect Not cause global warming Both Generate electricity Expense associated Increased demand Impact on environment – eg land Non renewable Already have facilities to extract Causes greenhouse effect Many environmental concerns. Causes global warming 5. Compare renewable and non-renewable resources.
6. Describe why rocks and soil are non- renewable resources. Being worn down or destroyed at a greater rate than they are being replaced. It takes millions of years for rocks to form. Soil is made from broken rock. 7. What does water-holding capacity refer to? Water holding capacity refers to the amount of water soil can hold. 8. What are the characteristics of soil with a high water holding capacity? The smaller the soil particles the higher the water holding capacity. This is because the soil is more compact and there are less spaces for the water to drain through. The larger the soil particles the more gaps there are for water to drain through. Plants require well drained soils so the water can reach their roots.
9. Classify the following as renewable or non-renewable: Living things are Renewable Living things include plants which are Renewable Water is Renewable Sand is Non-Renewable
10. Describe the process (chemical equation) of photosynthesis. Carbon Dioxide Water Glucose Oxygen Carbon Dioxide + Water Glucose + Oxygen
11. List the different types of renewable energy sources Hydroelectricity Wave/Tidal Energy Solar Power Geothermal Biofuel Wind Power 12.Describe how geothermal energy works. Molten rock under the earth’s surface is used to produce electricity. 13. State one advantage of using geothermal energy. No greenhouse gas emissions are produced 14. State one disadvantage of geothermal energy: Limited to certain areas and can result in pollutant gases escaping from below the Earth’s surface
15. Explain the term biomass. Give an example of how it can be used as an energy source. Biomass describes energy that is obtained from materials such as dead plants, plant matter, or animals and their wastes. These materials contain stored energy captured from the Sun. Eg dead plants and animals 16. Describe how fossil fuels are formed Fossil fuels such as coal, oil and gas are formed from dead animals and plants. These take millions of years to form. 17. Describe why are nuclear energy considered to be non- renewable source of energy. Uranium and Plutonium undergo a chain reaction in a process called nuclear fission 18. State one advantage of using nuclear energy. Nuclear power plants do not produce greenhouse gas emissions 19. State one disadvantage of nuclear energy. Nuclear energy produces wastes that remain active for millions of years.
20. Describe the difference between erosion and weathering. 21. Name 3 agents of erosion.22. Describe 3 main factors that cause weathering Water, Ice Changes in temperature - Water settles in cracks in rocks, as water freezes into ice it expands (gets larger), widening the crack Wind Running water and waves can gradually wear away rocks Strong winds blast rocks with small rock particles Air Natural chemicals in the air, soil and water attack substances in the rock (acid rain)
23. Describe the water cycle (label diagram). Evaporation Run-off Transpiration Condensation Precipitation Percolation
24. Describe the following terms: (a) evaporation process when water changes into water vapour (gas) from the suns energy (b) condensation process when water vapour turns into liquid water as it cools (clouds) (c) precipitation rain, snow, sleet, or hail that falls to the ground (d) transpiration the evaporation of water from plants (e) percolation the process of water soaking into the soil
25. Describe three things that affect the water cycle States of water (solid, liquid or gas) Air temperature Humidity Air movement Amount of sunshine 26. Describe the process of transpiration. Loss of water from a plant 27. Name 3 factors affecting transpiration. Wind, temperature (heat), humidity