Matter And Classification (Materials)

Question 1

What is matter made up of

Answer 1

Of particles whose properties determine the observable characteristics of matter and its reactivity

Question 2

Properties of materials (know definitions)

Answer 2

Strength

Brittle- hard but likely to break easily

Malleable - ability to be hammered or pressed into shape without breaking or cracking

Ductile - ability to be stretched into a wire

Density - the mass per unit volume of a substance

Melting point - the temperature at which a solid, given sufficient heat, becomes a liquid

Boiling point - The temperature of a liquid at which its vapour pressure equals the external (atmospheric) pressure

Question 3

What is a homogenous mixture

Answer 3

A mixture of uniform composition and in which all components are in the same phase

Eg. A solution of salt and water

Question 4

What’s a heterogeneous mixture

Answer 4

A mixture of non-uniform composition and of which the components can be easily identified

Eg, sand and water

Question 5

Examples of heterogeneous mixtures

Answer 5

Air
Black tea or coffee
Brine
Steel

Question 6

Heterogeneous mixture

Answer 6

Sand and rock mixture
Pizza toppings
Peanuts and raisins
Stones in concrete

Question 7

What’s an element

Answer 7

A pure substance consisting of one type of atom

Question 8

What’s a compound

Answer 8

A pure substance consisting of two or more different elements

Question 9

Define pure substance

Answer 9

A substance that cannot be separated into simpler components by physical methods

Question 10

Electrical conductor

Answer 10

A material that allows the flow of charge

Eg. Electrical cables

Question 11

Semiconductor

Answer 11

A substance that can conduct electricity under some conditions, but not others, making it a good medium for the control of electrical current

Question 12

Electrical insulators

Answer 12

A material that prevents the flow charge

Question 13

Define thermal conductor

Answer 13

A material that allows heat to pass through easily

Question 14

Define thermal insulator

Answer 14

Does not allow heat to pass through it

Question 15

Use of magnets in daily life

Answer 15

Speakers
Telephones
Electric motors
Compasses

Question 16

Physical methods of separating mixtures

Answer 16

Hand-sorting
Filtration
Evaporation
Distillation

Question 17

What’s an emulsion

Answer 17

A mixture obtained when one liquid is shaken up with another in which it cannot dissolve

Eg. Oil with vinegar in a salad dressing

Question 18

What’s a suspension

Answer 18

A mixture of solids floating in a fluid

Eg. Muddy water

Question 19

Ways to test If a substance in pure

Answer 19

The melting or boiling point of a substance

Paper chromatography

Question 20

Position of metals on Periodic Table

Answer 20

Metals compromise 4/5 of all elements and are found on the left side if the Periodic Table

The group of metals in the middle are called the transition metals

Question 21

Position of non-metals on the Periodic Table

Answer 21

The non-metals comprise a much smaller number of elements and are found on the right side of the Periodic Table

Question 22

Uses of Metalloids

Answer 22

Transistors
Microchips in computers
Calculators

Question 23

Position of Metalloids on Periodic Table

Answer 23

They are found on either side of the step that separates the metals from the non metals