Topic 1 - Atoms, Elements and Compounds

Question 1

What is an atom?

Answer 1

The smallest part of a chemical element that can exist.

Question 2

What is the relative mass of each particle?

Answer 2

Proton - 1. Neutron - 1. Electron - 0 (or very small)

Question 3

What is the charge of each particle?

Answer 3

Proton : +1. Neutron : 0. Electron : -1

Question 4

What is an element?

Answer 4

A substance made up of atoms with the same number of protons.

Question 5

What is an isotope?

Answer 5

A different form of an element - it has a different number of neutrons

Question 6

Balance this equation. Mg + O2 –> MgO

Answer 6

2Mg + O2 –> 2MgO

Question 7

What is a compound?

Answer 7

Substances formed from two or more elements.

Question 8

Give the formula for the following compounds:

Carbon Dioxide, Sodium chloride, Hydrochloric acid, Ammonia and Surfuric acid.

Answer 8

CO2, NaCl, HCl, NH3 and H2SO4

Question 9

What is the atomic mass number?

Answer 9

The amount of neutrons and protons in the nucleus of the atom.

Question 10

What is an ion?

Answer 10

A charged particle that is formed when an atom, or group of atoms, loses or gains electrons.

Question 11

What is the only way to separate a compound?

Answer 11

Via a chemical reaction.

Question 12

What are the half equations for the electrolysis of sodium chloride?

Answer 12

Cathode - 2H+ + 2e- –> H2

Anode - 2Cl- –> Cl2 + 2e-

Question 13

Write the ionic equation for the electrolysis of Sodium chloride

Answer 13

2H+ + 2Cl- –> H2 + Cl2