Y9 - Reactivity Flashcards
Chemical Change
Hard to reverse
1 or more new products
reactants used up
often light / fizzing / sound occurs
e.g - wood burning
Physical Change
easily reversible
no new products
often just a change in state
e.g - water freezing
Define implosion
An object being destroyed by collapsing in on itself
Define explosive
a substance that reacts very fast, releasing a lot of energy and gas
Define pressure
The amount of force pushing on a certain area. It is a way of saying how spread out a force is.
What happens when a metal reacts with water?
it produces a metal hydroxide and hydrogen
What happens when a metal reacts with oxygen?
A metal oxide is formed
What happens when a metal reacts with acid?
it produces a salt and hydrogen
What causes rusting?
When iron reacts with air and water forming iron oxide and damaging the structural integrity
How can rust be prevented?
Coating in paint
Coat or submerge in oil
Drying agent to eliminate moisture
Sacrificial metal - a more reactive metal that reacts first
Exothermic
a reaction that gives out energy
Endothermic
a reaction that takes in energy
What is a displacement reaction?
When a more reactive metal swaps places with a less reactive metal in a salt
Who invented dynamite?
Alfred Nobel
Ways of extracting metals from ores
Heating them with Carbon (Zinc, Iron, Tin, Lead, Copper, Silver, Gold)
Electrolysis
Reduction using a more reactive metal
