S3 - Chemistry Test (2)

Question 1

What is the formula mass and how is it obtained?

Answer 1

• The mass of all the atoms in a formula
• By adding the R.A.M of each atom

Question 2

What is 1 mole equal to in chemistry?

Answer 2

1 gram formula mass

Question 3

What does ‘a.m.u’ stand for?
Where do we most commonly put it?

Answer 3

• Atomic Mass Units
• After the formula mass

Question 4

What charge do the following have:
- Neutrons
- Protons
- Electrons

Answer 4

• No charge
• Positive
• Negative

Question 5

The atomic number of an atom is equal to the number of…

Answer 5

Protons and electrons

Question 6

What is the centre of an atom called and what charge does it have?

Answer 6

• The nucleus
• Positive charge

Question 7

Where are the following found in an atom:
- Neutron
- Proton
- Electron

Answer 7

Neutrons and Protons = Nucleus
Electron = Orbiting the nucleus

Question 8

Atoms have the same number of…

Answer 8

Protons and electrons

Question 9

What is the group number in the periodic table equal to?

Answer 9

The number of outer electrons

Question 10

What is the mass of the following:
- Neutron
- Proton
- Electron

Answer 10

• 1
• 1
• 0

Question 11

How do we work out the Mass numbers?

Answer 11

No. of protons + No. of neutrons

Question 12

What do all elements need to be?

Answer 12

Stable

Question 13

What group of the periodic table are stable?

Answer 13

The Noble Gases

Question 14

What do elements need to have to be stable?

Answer 14

A full outer shell of electrons

Question 15

What do elements need to do to create a full outer shell?

Answer 15

Share / steal electrons

Question 16

What happens when 2 non-metal atoms share electrons?

Answer 16

A molecule is formed

Question 17

What is a shared pair of electrons called?

Answer 17

A covalent bond

Question 18

Covalent network substances are…

Answer 18

Solid at room temperature, usually very hard and have high boiling points

Question 19

Do covalent network substances react?

Answer 19

No, they are unreactive

Question 20

What are the covalent network substances?

Answer 20

Boron, Carbon (in the form of diamond and graphite) & silicon

Question 21

What do non-metal atoms do to form a full outer shell of electrons?

Answer 21

Steal electrons form metals

Question 22

What do metals do to achieve a full outer shell of electrons?

Answer 22

Give electrons away

Question 23

How do we tell if a substance is ionic or covalent?

Answer 23

If the substance contains a metal it is ionic

Question 24

What happens to ionic substances that doesn’t to covalent?

Answer 24

They dissolve in other substances

Question 25

How do we work out the number of: - Protons - Electrons - Neutrons In an atom?

Answer 25

- Protons = Atomic No. - Electrons = Atomic No. - Neutrons = Mass No. — Atomic No.

Question 26

What is an ion?

Answer 26

An atom with a different number of protons and electrons due to electrons being shared / stolen to form a full outer shell in an atom

Question 27

What is an ionic bond?

Answer 27

The electrostatic force of attraction between a positively charged metal ion and a negatively charged non-metal ion

Question 28

How do we tell if an element is positively or negatively charged?

Answer 28

If the atom gives away an electron to gain a full outer shell of electrons it is positively charged as it has less electrons than protons. If an atom steals electrons it is negatively charged as it has more electrons than protons

Question 29

What is a covalent bond?

Answer 29

A shared pair of electrons

Question 30

Do covalent molecular and network substances conduct electricity?

Answer 30

No, this applies in any matter as well

Question 31

Do ionic substances conduct electricity?

Answer 31

They are poor conductors as a solid but conduct well when molten or in solution.

Question 32

Ionic substances have low melting points - True or False

Answer 32

False

Question 33

What is the only type of compound with a low melting point?

Answer 33

Covalent molecule

Question 34

The only type of compound to conduct as a solid is…

Answer 34

Metallic lattice