Air and Water

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Across
  1. 5. Turns blue in the presence of water
  2. 6. When the water is passed through filter beds to remove different sized insoluble solids
  3. 7. used to separate nitrogen and oxygen in liquid air
  4. 9. When the water is then sterilised, to kill microbes
  5. 10. Form by the combustion of leaded petrol
  6. 11. Form by the incomplete combustion of carbon-containing substances
  7. 12. ______ water helps the body to stay hydrated
  8. 13. Water is used as a ______ in industries
  9. 15. Covers more than 70% of the Earth
Down
  1. 1. Covers 78% of the air
  2. 2. Form by combustion of fossil fuels which contain sulfur compounds
  3. 3. Turns pink in the presence of water
  4. 4. Used to remove oxides of nitrogen
  5. 8. Form from the heat and pressure found in a car engine
  6. 14. Covers 21& of the air