Karteikarten
Science Flashcards
Karten in diesem Stapel (4)
- 1Conditions affecting the Haber process.The raw materials for this process are hydrogen and nitrogen. Nitrogen and hydrogen will react together under these conditions:
- A high temperature around 450ºC.
- A high pressure around 200 atmospheres (200 times normal pressure).
- An iron catalyst. - 2Evidence regarding plate tectonics.Wegeners evidence regarding his theory on plate tectonics:
-Plate tectonics explained why earthquakes and volcanoes were concentrated in specific places usually around the boundaries of moving plates.
- The match in shape between the east coast of South America and the west coast of Africa suggests both were once part of a single continent. There are similar patterns of rocks and similar fossils on both sides of the Atlantic.
- Thanks to Wegeners evidence on plate tectonics we now know our continents used to be connected and our planet used to be called Pangea.
- 3Fertilisers.Fertilisers make crops grow faster and bigger so that crop yields are increased. They are water-soluble minerals. They must be able to dissolve in water so that plants can absorb them through their roots. Fertilisers provide plants with the essential chemical elements needed for growth particularly nitrogen, phosphorus and potassium.
- 4Eutrophication.A major problem with the use of fertilisers occurs when they're washed off the land by rainwater into rivers and lakes. The resulting increase of nitrate or phosphate in the water encourages algae growth, which forms a bloom over the water surface. This prevents sunlight reaching other water plants, which then die. Bacteria break down the dead plants and use up the oxygen in the water so the lake may be left completely lifeless.
