Redox, thermal decomposition and chemical tests

Question 1

Key chemical tests

Carbon dioxide - Limewater test

Answer 1

Bubble in to limewater.

Clear to cloudy = carbon dioxide

Question 2

Oxygen- Glowing splint test

Answer 2

A glowing splint will relight with oxygen

Question 3

Hydrogen- Squeaky pop test

Answer 3

A lit splint will cause a mini explosion with hydrogen

Question 4

Key chemical tests:

Water- Anhydrous Copper Sulfate

Answer 4

Goes from white powder to blue powder

Cobal chloride paper goes blue to pink

Question 5

Key reaction types.

Oxidation

Answer 5

The addition of oxygen to an element or compound

Magnesium + oxygen – magnesium oxide

Question 6

Key reaction types

Reduction

Answer 6

The loss of oxygen from a compound

Copper oxide + carbon –> copper+ carbon dioxide

This is redox

Question 7

Key reaction types

Redox

Answer 7

Oxidation and reduction happen at the same time

Iron oxide + Carbon –> Iron + carbon dioxide

Question 8

Key reaction types

Thermal decomposition

Answer 8

The use of heat to break down compounds into simpler elements and compounds

Copper carbonate–> Copper oxide + carbon dioxide

Hydrated copper sulfate