Summer Revision 2020 Past Paper

Question 1

Oxidation is the ____ of electrons.
Reduction is the ____ of electrons.

Answer 1

losing
gaining

Question 2

Why should carbon electrodes be continually replaced?

Answer 2

Because oxygen reacts with carbon in the positive electrodes, forming carbon dioxide.
So they gradually burn away.

Question 3

How many atoms are joined by one diamond atom?

Answer 3

One atom is joined by 4 other carbon atoms.

Question 4

What are the 4 physical properties of diamond?

Answer 4

Diamond has a high melting point, high boiling point, is very hard and can’t conduct electricity.

Question 5

Why is diamond hard?

Answer 5

Because the carbon atoms are held together by STRONG covalent bonds.

Question 6

Why do giant covalent structures have a high melting/ boiling point?

Answer 6

This is because a large amount of energy is needed to overcome the strong covalent bonds.

Question 7

What are examples of giant covalent structures?

Answer 7

Diamond,
Graphite,
Silicone Dioxide

Question 8

In the thermal decomposition of metal carbonates practical, the more ______ the metal is, the more _____ the metal carbonate is.

Answer 8

reactive
stable

Question 9

How can the stability of metal carbonates be measured in the thermal decomposition of metal carbonates practical?

Answer 9

By heating the carbonate and bubbling the produced carbon dioxide through limewater.

Question 10

In the thermal decomposition of metal carbonates practical:
The quicker the limewater becomes milky, the greater the ___________________. Meaning the carbonate is ___________.

Answer 10

rate of decomposition
less stable

Question 11

In the thermal decomposition of metal carbonates practical, you should set up what equipment?

Answer 11

A Bunsen burner, test tubes, tripod and gauze.

Question 12

After setting up equipment for the _ the student should ____________________ and _____________________ until there is no further change in mass.

Answer 12

collect CO2 with a syringe
heat the metal carbonate

Question 13

In the thermal decomposition of metal carbonates practical, you should repeat __________________________________.

Answer 13

the experiment on different metal carbonates.

Question 14

Why should you repeat 3 times in the thermal decomposition of metal carbonates practical?

Answer 14

To reduce anomalies.

Question 15

What is the equation for moles?

Answer 15

number of moles= mass/ relative formula mass

Question 16

What is a mole?

Answer 16

The amount of substance that contains the same number of particles as the atoms.

Question 17

What is the molar volume of gas?

Answer 17

The volume occupied by one mole of gas at room temperature and pressure.

Question 18

What is the volume of gas of one mole at room temperature and pressure?

Answer 18

24dm3

Question 19

What is the equation for volume of gas at rtp?

Answer 19

Volume of gas= Number of moles x 24

Question 20

What are the steps for calculating the mass of chlorine?

Answer 20

1. Find moles of gold with the formula: moles= mass/ rfm
2. Use the 2:3 ratio to find moles of chlorine.
3. Multiply by mr (using cl2)