Unit 1

Question 1

What factors affect the rate of a chemical reaction?

Answer 1

temperature
concentration
surface area
presence of a catalyst

Question 2

What is an electron?

Answer 2

A negatively charged particle that spin around the positive centre of the atom. Their mass is so small that it is almost zero.

Question 3

What is a proton?

Answer 3

A positively charged particle that ave found in the nucleus of the atom. They have a mass of 1.

Question 4

What is a neutron?

Answer 4

Neutrons are found in the nucleus but have no charge. They have a mass of 1.

Question 5

What is an isotope?

Answer 5

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

Question 6

What is an ion?

Answer 6

An ion is a charged particle that is formed when an atom gains or loses electrons.

Question 7

What form positive or negative ions?

Answer 7

Metal atoms lose electrons to form positive ions.

Non-metal atoms gain electrons to form negative ions.

Question 8

Group 8 elements don’t react with other elements, why?

Answer 8

Noble gases (group 8 elements) have a full outer shell of electrons so they are stable and don’t react.

Question 9

What is a molecule?

Answer 9

A molecule is two or move atoms joined together by covalent bonds.

Question 10

What is a covalent bond?

Answer 10

A covalent bond is a shared pair of electrons between two non-metal atoms.

Question 11

What is a diatomic molecule?

Answer 11

A diatomic molecule is a molecule that contains two atoms only.

Question 12

What is an ionic bond?

Answer 12

An electrostatic force of attraction between positive metal ion and negative non-metal ion.

Question 13

What structure do ionic compounds form?

Answer 13

An ionic lattice

Question 14

Can ionic compounds conduct electricity?

Answer 14

Only when molten or in solution because the ions must be free to move.

Question 15

Can ionic compounds dissolve in water?

Answer 15

Yes.

Question 16

What are the bp and mp for an ionic compound?

Answer 16

They have a nigh melting and boiling point due to the strong ionic bonds that require lots of energy to break.

Question 17

What are the properties or a covalent network substance?

Answer 17

• They have high melting and boiling points.
• They have strong covenant bonds.
• don’t conduct electricity, except for graphite it has delocalised electrons)

Question 18

What are the properties of covalent molecules?

Answer 18

• strong bonds within molecules but weak bonds between them.
• don’t conduct electricity with the exception of water.
• low melting and boiling points.

Question 19

When is an acidic solution produced?

Answer 19

When a soluble non-metal is dissolved in water.

Question 20

What is a base?

Answer 20

A soluble metal oxide.

Question 21

When is an alkaline solution produced!

Answer 21

When a soluble metal oxide is dissolved in water.

Question 22

What are neutral solution?

Answer 22

Solutions that contain equal amounts of hydrogen and hydroxide ions.

Question 23

What is produced when an acid+ alkali react?

Answer 23

Salt + water

Question 24

What is produced when acid + base react?

Answer 24

Salt + water

Question 25

What is produced when acid + metal carbonate react?

Answer 25

Salt + water + carbon dioxide

Question 26

What is a precipitate?

Answer 26

An insoluble solid made from two liquids.