Chemical Changes

Question 1

Metal + water

Answer 1

Metal Hydroxide(alkali) + hydrogen

Question 2

Metal + hydrochloric acid

Answer 2

Metal chloride + hydrogen

Question 3

Metal hydroxide + nitric acid

Answer 3

Metal nitrate + water

Question 4

Oxidation reaction is

Answer 4

Loosing electrons

Question 5

Reduction reaction is

Answer 5

Gaining electrons

Question 6

Redox reaction

Answer 6

When a reduction and oxidation reaction occur at the same time

Question 7

Metal Oxide + sulfuric acid

Answer 7

Metal sulfate + water

Question 8

acid + carbonate

Answer 8

Salt + water + carbon dioxide

Question 9

What do acids produce in aqueous solutions

Answer 9

H+ ions

Question 10

What do alkali produce in aqueous solutions

Answer 10

OH- ions

Question 11

How to make Copper sulfate crystals from copper oxide

Answer 11

1.Put excess copper oxide into sulfuric acid in a beaker
2. Filter solution
3. Place the solution in an evaportaing basin
atop a beaker with water in which is being boiled above a bunsean burner
4. Evaporate half of liquid
5. Pour remaining liquid into dish and wait a day or 2

Question 12

Difference between strong and weak acid

Answer 12

Strong acids fully ionise in a solution weak ones don’t
Strong H+ Cl-
Weak CH3COO- H+

Question 13

How to set up an electrolysis

Answer 13

Place Cathode and Anode rods in electrolyte
The 2 rods are differently charged becasue they are connected to different terminals
Due to electrostatic force the negative ions go to the positive electrode and vise versa
The charges between the ions are excanged through the circuit and elements are formed at each electrode

Question 14

What is an electrolyte

Answer 14

An ionic liquid that conducts electricity

Question 15

What are electrodes made of and why

Answer 15

Graphite so they don’t react with ions

Question 16

Rule for what is deposited at CATHODE

Answer 16

If the metal ions are MORE reactive than hydrogen- hydrogen is produced
If they are LESS reactive the metals are made

Question 17

In what case would you use electrolysis to extract a metal

Answer 17

If the metal is more reactive than carbon and therefore cannot be displaced by it

Question 18

When using electrolysis on aluminium oxide what should be done

Answer 18

Add molten cryolite to lower its boiling point

Question 19

Rule for what is deposited at ANODE

Answer 19

If halogens are present halogens are made
If halogens aren’t present oxygen is made

Question 20

How to do a titration on sodium hydroxide

Answer 20

1. Pour 25cm3 of sodium hydroxide solution into a conical flask
2. Add drops of phenolphthalein (literally just indicator) to conical flask
3. Swirl flask, mixture turns pink
4. Place concial flask on white tile
5. Clamp a burette to a stand and fill it to 0cm3 of sulfuric acid
6. Place burette over concial flask
7. Open burette so acid flows out
8. Add acid until indicator is colourless
9. Record amount of acid added to sodium hydroxide