C1 - Atomic Structure

Question 1

How do you work out the number of electrons, protons and neutrons in an atom?

Answer 1

The atomic number in the periodic table represents the

number of protons which is equal to the number of electrons. Mass number – Atomic number = neutron number

Question 2

Why are few objects made of pure metals?

Answer 2

Pure metals often are too expensive. In a pure metal the

atoms are arranged in layers. The layers can slide easily which means that the metal bends too easily.

Question 3

Why is there no overall charge on an atom?

Answer 3

because the number of positive protons and negative electrons is equal in an atom.

Question 4

Why do all atoms in the same group have similar chemical properties?

Answer 4

Because they all have the same number of electrons in their outer shell.

Question 5

Why are all group 0 atoms unreactive?

Answer 5

Because they all have a full outer shell.

Question 6

What are the differences in the atomic structure of hydrogen and helium atoms?

Answer 6

Hydrogen has 1 electron whereas helium has 2 electrons.

Hydrogen has 1 proton and 0 neutrons, helium has 2 protons and 2 neutrons.

Question 7

How many electrons can you fit on each shell around the nucleus of an atom?

Answer 7

electrons on the first (inner shell), then 8 on the second and third shell.

Question 8

Describe the following reaction in terms of the
names of the substances and the number of atoms
involved: 2Al + 3Cl2 –> 2AlCl3

Answer 8

2 aluminium a toms react with 3 chlorine molecules to form 2 aluminium chloride molecules.