Atomic Structure

Question 1

What give an element its chemical and physical properties?

Answer 1

The structure of the atom is what gives an element its chemical and physical properties.

Question 2

Name the three smaller particles that make up an atom

Answer 2

The three smaller particles that make up an atom are protons, neutrons and electrons

Question 3

Explain what protons are

Answer 3

Protons are positively charged particles that are contained in the nucleus of the atom (the centre) they have a mass of 1 amu (atomic mass unit).

Question 4

Explain what neutrons are

Answer 4

Neutrons are particles with no charge that are also contained in the nucleus of the atom. They also have a mass of 1 amu.

Question 5

Explain what electrons are

Answer 5

Electrons are negatively charged particles that spin around the positive centre of the atom in circles called energy levels. Their mass is so small it is nearly zero.

Question 6

Describe what an atom looks like

Answer 6

An atom contains protons and neutrons in the centre of the atom which is known as the nucleus. Electrons orbit the central nucleus. The atom has electrons in the outer energy levels.

Question 7

What overall charge does the nucleus have?

Answer 7

The nucleus has an overall positive charge as it contains the protons.

Question 8

State the mass, charge and location of an electron

Answer 8

An electron has:
a mass of approximately 0
a negative charge (-1)
and is located in the energy level

Question 9

State the mass, charge and location of a neutron

Answer 9

A neutron has:
a mass of 1 atomic mass unit
a neutral charge (0)
and is located in the nucleus

Question 10

State the mass, charge and location of a proton

Answer 10

A proton has:
a mass of 1 atomic mass unit
a positive charge (+1)
and is located in the nucleus

Question 11

What overall charge does an atom have and explain why?

Answer 11

Every atom has no overall charge (neutral). Atoms contain charged particles, they have the same number of positive protons as negative electrons. These opposite charges cancel each other out making the atom neutral.

Question 12

Describe elements in the same group

Answer 12

Elements in the same group have similar chemical properties. This is because they have the same number of outer electrons and the same valency.

Question 13

What is the name given to elements in group 1?

Answer 13

The elements in group 1 are known as alkali metals.

Question 14

Describe the properties of elements in group 1

Answer 14

They react rapidly (very fast) with water, producing an alkaline solution and hydrogen gas. The metals become more reactive as you go down the group.

Question 15

What is the name given to elements in group 7?

Answer 15

The elements in group 7 are known as halogens

Question 16

Describe the properties of elements in group 7

Answer 16

Fluorine and chlorine are gases. Bromine is one of only two liquid elements. Iodine is solid. They exist as diatomic molecules - they have two atoms in each molecule. As you go down the group the halogens become less reactive.

Question 17

What is the name given to elements in group 0 (group 8)?

Answer 17

The elements in group 0 are known as noble gases.

Question 18

Describe the elements in group 0 (group 8)

Answer 18

They are very unreactive and exist as individual atoms (monatomic).

Question 19

What is the name given to elements which are found between groups 2 and 3?

Answer 19

The transition metals are elements which are found between groups 2 and 3.

Question 20

Describe the elements which are found between groups 2 and 3

Answer 20

Well known examples are iron, copper and gold. They are generally quite dense (heavy) and many form brightly coloured compounds.

Question 21

What does the atomic number of an element tell you?

Answer 21

The atomic number of an element tells you how many protons that the element has. This is written at the bottom left hand side of the symbol.

Question 22

How many electrons can each energy level of an atom hold?

Answer 22

The first energy level (the one nearest the nucleus) can hold a maximum of two electrons with the others being able to hold up to a maximum of 8 electrons (only true for the first 20 elements).

Question 23

Explain how the number of outer electrons affects an element

Answer 23

It is the number of outer electrons that give an element its chemical properties. This is why elements in the same group of the Periodic Table have similar properties.

Question 24

Where is the mass number given on the elements symbol?

Answer 24

The mass number is given at the top left of the elements symbol

Question 25

What does the mass number tell us?

Answer 25

The mass number of an element tells us the number of protons AND neutrons in an atom (the two particles that have a measurable mass).

Question 26

What are isotopes?

Answer 26

Isotopes are atoms with the same atomic number but different mass number.

Question 27

What are elements made up of and what is the mass given in the data booklet called?

Answer 27

Elements are made up of isotopes so the mass given in the data booklet is called the relative atomic mass (RAM).

Question 28

What does the relative atomic mass shown in the data booklet, take into account?

Answer 28

The relative atomic mass of each element shown in the data book is calculated from the masses of all the isotopes of an element taking into account the percentage proportion of each.

Question 29

Example:
There are two isotopes of chlorine, chlorine-35 and chlorine-37. The relative atomic mass of chlorine is 35.5, what does this tell us?

Answer 29

Since the relative atomic mass of chlorine is 35.5, chlorine-35 must be more abundant because its mass number is closer to the relative atomic mass.