Topic 5 - chemical changes Flashcards
How can metals be placed in order of reactivity?
By their reactions with water and dilute acid
Why gas is given off when metals react with water or dilute acids?
Hydrogen
What does OIL RIG stand for?
Oxidation Is Loss of electrons
Reduction Is Gain of electrons
What are metal ores?
A rock with enough metal or metal compound in it to make it worth extracting from the ground
What is a metal compound?
A metal found in the ground which is chemically combined with other elements. This mean it has to be chemically separated before it can be used
Why would they not mine the ore if there isn’t enough?
It isn’t economic
What needs to happen to some ores before they can be used?
They need to be concentrated, and then the metal is extracted and purified
What is one example of an unreactive metal that can be found in their native state?
Gold
How does the reactivity series help decide the best way to extract a metal from its ore?
The oxide is metals below carbon in the series can be reduced by carbon to give the metal element
How do you extract a metal more reactive than carbon?
By using electrolysis
What is salt?
A compound formed when the hydrogen in an acid is replaced by metal or ammonium ions
Salts can be made by reacting a suitable metal with what?
An acid
Does the metal to make salt have to be above or below hydrogen in the reactivity series?
It has to be above but not dangerously reactive
How do you find a sample of the salt?
By evaporating off the water
What happens when an acid reacts with a base?
Neutralisation occurs
