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Unit 13 The Water Planet,The Properties of Water,Questions for listening,Oceans: _,Marian life: _species,99,5 million,Chemical structure,Water molecule structure: Influence,Two hydrogen atoms and one oxygen atom,1.It can break down both solids and gases,2. The chemical structure also makes it different from almost everything else on earth,Salinity,The salinity of the earths ocean: Influence,About 35 parts per thousand,Affects both its weight and freezing point,heavier than pure water,lower than pure water,Density,Definition: Measurement: The density of pure water: Influence: The change when being frozen,It is the relationship between mass and volume,Kilogrammes per cubic meter (kg/m3,1,000 kg/m3,Make the marine animals float around the sea,Its density decreases,Heat capacity,Definition: The heat capacity of water: Influence,It is the amount of energy it takes to raise the temperature of a substance by one degree centigrade,Relatively high,absorb and give off a lot of heat without big changes in temperature,Make a stable environment,Ocean motion,Ocean motion: Influence,It is always moving,Add the energy to the marine ecosystems and moves nutrients around,dense water,Less dense water
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