Different Types of Chemical Reactions (Part 3) Unit 2 Topic 3 Flashcards
When does rusting occur?
How can it be sped up?
Presence of oxygen and water
Salt
What is the chemical name and formula of rust?
Hydrated Iron Oxide
Fe2O3.xH2O
Name 3 deliquescent materials?
Calcium Oxide
Sodium Hydroxide
Calcium Chloride
Give 5 methods used to prevent rusting?
Painting Oiling Galvanising Tin Plating Stainless Steel
What is galvanising?
A process that bonds a layer of zinc metal onto the surface of steel.
Zinc reacts with air to form protective layer of zinc oxide.
Even if it becomes scratched, steel won’t rust as zinc reacts first.
What is sacrificial protection?
More reactive metal in contact with less reactive metal with react first and protect less reactive metal.
What is oxidation?
- Addition of oxygen to a substance
- Removal of hydrogen from a substance
- Removal of electrons from a substance
What happens when sulfur is burned in air?
Yellow, brittle solid. Burns with blue flame and forms gas sulfur dioxide.
What is reduction?
- Removal of oxygen from a substance
- Addition of hydrogen to a substance
- Addition of electrons to a substance
What happens when copper oxide is reduced?
Begins black. Changes to pink copper coloured substance during reaction. Condensation inside tube.
Why is excess hydrogen burned?
Prevent flammable hydrogen gas building up in the lab
What is a reducing agent?
A substance that will remove oxygen from a compound such as an oxide. It is oxidised!
What is an oxidising agent?
A substance that will add oxygen to a substance being oxidised. It is reduced!
What is a redox reaction?
Combined process of reduction and oxidation.
What is OILRIG?
Oxidation is loss of electrons, reduction is gain of electrons
