S2 Mystery of Substances

Question 1

What is an element?

Answer 1

An element contains only one type of atom.

Question 2

What is an atom?

Answer 2

An atom is the smallest building block in chemistry.

Question 3

What is a molecule?

Answer 3

A molecule is more than one atom chemically
bonded together.

Some elements naturally exist as molecules e.g. hydrogen and oxygen

Question 4

What is a compound?

Answer 4

A compound is two or more different elements chemically bonded together

Question 5

What is a mixture?

Answer 5

A mixture can contain different elements and compounds which are not chemically bonded.

Question 6

Describe this substance.

Answer 6

It is an element - there is only one type of atom.

Question 7

Describe this substance.

Answer 7

It is a compound - there is two different types of atom bonded together.

Question 8

Describe this substance.

Answer 8

It is a molecule of an element - there is only one type of atom, and it is bonded together.

Question 9

Describe this substance.

Answer 9

This is a mixture of elements.

One element is a single atom, the other element is a molecule.

Question 10

Describe this substance.

Answer 10

It is a mixture of compounds.

Question 11

Describe this substance.

Answer 11

It is a mixture of elements and compounds.

Question 12

How are elements in the periodic table arranged?

Answer 12

They are arranged in order of increasing atomic number.

Question 13

What are some properties of metals?

Answer 13

• Shiny
• Conduct electricity
• Conduct heat
• Malleable
• Almost all are solid (except mercury)
• They have high melting/boiling points

Question 14

What are some properties of non-metals?

Answer 14

• They are dull
• Poor conductors of heat
• They have low melting points
• Are not magnetic

Question 15

What are the two elements which are liquid at room temperature?

Answer 15

Bromine and mercury.

Question 16

This group of the periodic table contains highly reactive solids, which reveal a shiny surface when cut.

Which group is it?

Answer 16

Group 1 - Alkali Metals

Question 17

This group of solids do not cut easily, and do not react quickly with water.

Which group is it?

Answer 17

Group 2 - Alkali Earth Metals

Question 18

The reactivity of this group of non-metals decreases as you go down the group.

Which group is it?

Answer 18

Group 7 - Halogens

Question 19

The elements in this group are colourless gases. They are highly unreactive.

Which group is it?

Answer 19

Group 8/0 - Noble Gases

Question 20

The elements in this group are very unreactive, but they are very strong and dense. One of the elements in this group is a liquid.

Answer 20

Transition Metals

Question 21

What is the name of the compound containing magnesium and oxygen?

Answer 21

Magnesium oxide

Question 22

What is the name of the compound containing sodium and chlorine?

Answer 22

Sodium chloride

Question 23

What is the name of the compound containing lithium and nitrogen?

Answer 23

Lithium nitride

Question 24

What are the elements contained in calcium sulfide?

Answer 24

Calcium and sulfur

Question 25

What is required to break a compound up into its constituent elements?

Answer 25

Energy

Question 26

What is the name of the process which separates a compound into its elements using electricity.

Answer 26

Electrolysis

Question 27

What is the word equation for the following reaction:

When sodium burns, it reacts with oxygen in the air to make sodium oxide.

Answer 27

Sodium + Oxygen -> Sodium Oxide