chapter 2 key terms

Question 1

alloy

Answer 1

A substance formed when other materials
(e.g. carbon, other metals) are mixed with a
metal.

Question 2

aqueous

Answer 2

The solution resulting when a chemical

species has been dissolved in water (aq)

Question 3

atom

Answer 3

The basic building block of matter. It is made up of subatomic particles—protons, neutrons and electrons.

Question 4

atomic theory of matter

Answer 4

theory proposed by John Dalton in 1802 that states that all matter is made of atoms. He said that atoms are indivisible, atoms of the same element are identical and compounds are made up of different types of atoms in fixed ratios

Question 5

chemical symbol

Answer 5

A symbolic representation of an element, usually one or two letters, where the first letter is capitalised and the second letter
is lower case

Question 6

Component

Answer 6

Each chemical in a mixture. The components can be separated by chromatography.

Question 7

compound

Answer 7

A pure substance made up of different types of atoms combined in a fixed ratio.

Question 8

covalent network structure

Answer 8

An arrangement of atoms in a network in which there are strong covalent bonds between the atoms in three dimensions

Question 9

crystallisation

Answer 9

The process in which solid crystals are deposited when the concentration of a solute in a solution increases past the point of saturation.

Question 10

decanting

Answer 10

A separation technique in which a layer of liquid is removed by carefully pouring it off from a settled solid or more dense immiscible liquid.

Question 11

discrete molecule

Answer 11

A definite number of atoms covalently bonded together with weak intermolecular forces.

Question 12

dissolved

Answer 12

Incorporated a solid or gas into a liquid so as to form a solution

Question 13

distillation

Answer 13

a method to separate a mixture of liquid components into individual liquid components. - The separation of liquids is based on the boiling points of the liquid components

Question 14

element

Answer 14

A substance made up of atoms with the

same atomic number.

Question 15

filtrate

Answer 15

The liquid that has passed through a

filter.

Question 16

fluid

Answer 16

A substance with no fixed shape; a liquid

or a gas.

Question 17

giant molecule

Answer 17

very large molecule formed by some non-metals, e.g. a large network of covalently bonded atoms, such as diamond or graphite.

Question 18

latent heat

Answer 18

The heat energy required to change the state of a substance without changing the temperature.

Question 19

latent heat of fusion

Question 20

latent heat of vaporisation

Answer 20

The energy required to change a fixed amount of solid to liquid at its melting temperature.The latent heat of fusion of water is 6.0 kJ mol−1, meaning 6.0 kJ of energy is needed to change 1 mol of water from a solid to a liquid at 0°C.

Question 21

matter

Answer 21

Anything that has mass and occupies space.

Question 22

metal

Answer 22

Metals are found on the left side and the centre of the periodic table

Elements that are crystalline when solid and many of which are characterised by opacity, ductility, conductivity, and a peculiar lustre when freshly fractured