Chemical changes Flashcards
What is the reactivity series
Potassium
Sodium
Lithium
Calcium
Magnesium
Aluminium
Carbon
Zinc
Iron
Tin
Lead
Hydrogen
Copper
Silver
Gold
Platinum
What happens when metals react with water
Reacts with water to form metal hydroxide and hydrogen gas
Metal + Water —> Metal Hydroxide + Hydrogen gas
What happens when metals react with dilute acid
A salt and hydrogen are formed
Metal + Acid —> Salt + Hydrogen gas
What happens when metals react with oxygen
Burn when heated as it reacts with oxygen
Copper forms a layer of copper oxide on the surface and doesn’t burn
Metal + Oxygen —> Metal Oxide
What is displacement
When a reactive metal will take the place of a less reactive metal in a compound
What is a redox reaction
When REDuction and OXidation takes place at the same time
What are the metals that can be extracted using carbon and how does it work
Metals below carbon in the reactivity series can be extracted by reduction using carbon, e.g. Iron Oxide is reduced in a blast furnace to make iron
What are the metals that can be extracted using electrolysis and how does it work
Metals above carbon in the reactivity series can be extracted by electrolysis
A current breaks it down
What is the difference between an acid and alkaline
Acid - a substance that produces more hydrogen ions than hydroxide ions when dissolved in water
Alkaline - a substance that produces more hydroxide ions than hydrogen ions when dissolved in water
What is neutral
A substance that is neither acid or alkaline
How can you tell if a substance is acid or alkaline
Universal indicator
Litmus paper
What are the three acids
Hydrochloric
Sulfuric
Nitric
What is a base
A substance that reacts with an acid to neutralise it and produce a salt and water
What happens when acids react with carbonates
A salt, water and carbon dioxide are produced when acids react with carbonates
Acid + Carbonate —> Salt + Water + Carbon Dioxide
Required practical : Making soluble salts from insoluble substances
What is the method
Add powdered soluble reactant to acid in a beaker, one spatula at a time, stirring to mix. Continue adding until there’s excess
Filter mixture in the beaker to remove the excess powder. Collect filtrate
Pour filtrate into an evaporating basin and put on a roaring blue flame until small crystals appear on the edge
