Question | Answer |
What is the atmosphere? | A layer of gases around the Earth, theses gases are known as air |
What gases are in the air and what are their concentrate? | Nitrogen=78%, Oxygen=21% and (Argon,carbon dioxide and water vapour=1%) |
What is a catalyst? | Substances that alter the rate of a chemical reaction but are not used up themselves |
What is the word equation for the perparation of oxygen? | Hydrogen peroxide --->manganese dioxide---> oxygen + water |
What is the chemical equation for the perparation of oxygen? | 2H2O --> MnO2--> O2 + 2H2O |
What is the result of the test for oxygen? | It relights a glowing splint |
What is the test for carbon dioxide? | Carbon dioxide turns limewater milky |
What is the word equation for the perparation of carbon dioxide? | Hydrochloric acid + calcium carbonate ---> calcium chloride + water + carbon dioxide |
What is the chemical equation for the perparation of carbon dioxide? | 2HCl CaCO3 ---> CaCl2 + H2O + CO2 |
What are the uses or carbon dioxide? | Refrigeration,stage effects,fire extinguishers and fizzy drinks |