Properties Of Matter

Question 1

What is the definition of an element?

Answer 1

Elements are pure substances composed entirely of one type of atom and therefore, cannot be decomposed into simpler substances.

Question 2

What are three examples of an element?

Answer 2

Carbon, Oxygen, Hydrogen etc.

Question 3

What is the definition of a compound?

Answer 3

Compounds are substances that contain 2 (or more) types of atoms which are chemically bonded
together in a fixed ratio, and therefore can be decomposed into simpler substances.

Question 4

What are three examples of compounds?

Answer 4

Salt - NaCl
Hydrochloric Acid - HCl
Water - H20

Question 5

What is the definition of a mixture?

Answer 5

Mixture are impure substances that contain a combination of different elements and/or
compounds. In mixtures, there is no fixed ratio of substances and therefore there can be variable
composition.

Question 6

What are the two different types of mixtures?

Answer 6

Homogenous and Heterogenous mixtures.

Question 7

What is a homogeneous mixture? Include an example?

Answer 7

Homogenous substances have uniform composition throughout. These substances are considered
pure. For example coco-cola and pure water (etc.)

Question 8

What is a heterogeneous mixture? Include an example?

Answer 8

Heterogeneous substances have non-uniform composition where there are substances or materials of different varieties. For example blood and soil (etc.)

Question 9

Draw and/or explain the visual composition of a heterogeneous and homogeneous mixture?

Answer 9

search up.

Question 10

What is a solution? What are the two main components?

Answer 10

A solution has one or more solutes that are dissolved in a solvent. A solvent is a substance in
which the solute dissolves and a solute is a substance that dissolves in a solvent.

Question 11

What is a common solvent and what are the characteristics?

Answer 11

Water as a solvent:
- Water is an excellent solvent.
§ Aqueous solutions are formed when a solid, liquid or gas is dissolved in water.

Almost all biological and industrial processes occur in water – these systems are known as aqueous environments.

Question 12

What happens when a substance is mixed with a solvent, but it doesn’t dissolve to form a solution?

Answer 12

It can form a suspension or a colloid.

Question 13

What is a suspension?

Answer 13

A suspension is a heterogeneous mixture, with visible distinguishable parts, that form when a
substance does not dissolve significantly.

Question 14

What are the characteristics of a suspension? And an example?

Answer 14

• non-uniform composition
• large particle size
• if left it will settle at the bottom

An example is sand in water or soil in water.

Question 15

What is a colloid?

Answer 15

A colloid is a mixture of particles that consists of smaller clusters of ions or molecules. They are
evenly dispersed throughout the solvent and do not settle on standing. It is a homogenous mixture.

Question 16

What are the changes in states for;

liquid --> solid
solid --> liquid
liquid --> gas
gas --> liquid
solid --> gas
gas --> solid

Answer 16

liquid --> solid = freezing
solid --> liquid = melting
liquid --> gas = boiling
gas --> liquid = condensation
solid --> gas = sublimation
gas --> solid = deposition

Question 17

Draw and/or explain the visual composition of a solid

state of matter? + Add the characteristics

Answer 17

• arranged in defined shape/ particles touching
• particles vibrate in their position
  + not very compressible as they are already compressed

Question 18

Draw and/or explain the visual composition of a liquid state of matter? + Add the characteristics

Answer 18

• takes shape of the container
• not confined by vibrations
• random translations from one position to
  another.
  + slight compression

Question 19

Draw and/or explain the visual composition of a gas state of matter? + Add the characteristics

Answer 19

• well separated; full space available
• more rapid movements
• no significant force between particles
  + very compressible as large space between particles

Question 20

What is important when drawing a diagram?

Answer 20

Drawing a Diagram

• use a pencil
• use a ruler
• labels with no arrowhead must be horizontal and touching equipment

Question 21

What method of separation would separate two solids different sized particles. What is the property enabling this separation?

Answer 21

Mixtures in which the particles of the different substances have different sizes can be
separated by sieving. The property enabling this separation is that it has different sized particles.

Question 22

What method of separation would separate an undissolved solid and a liquid. What is the property enabling this separation?

Answer 22

Filtration is a process where liquid or solution is passed through the filtration paper whilst the solid remains on top. The property enabling this separation is that it has particle size and solubility.

When a solid is coarser or denser, a process of sedimentation and decantation can be used.

Question 23

What method of separation would separate a dissolved solid and a liquid. What is the property enabling this separation?

Answer 23

When a solid is dissolved in a liquid, the mixture is called a ‘solution’ and therefore, filtration
techniques do not work.

Evaporation is a process of heating the liquid to a temperature below its boiling point so that the
liquid is slowly blown away into the air. Distillation can also be a method and is more accurate than evaporation. The property enabling this separation is the boiling point.

Question 24

What method of separation would separate immiscible liquids. What is the property enabling this separation?

Answer 24

Immiscible liquids are two or more liquids that do not mix to form a homogenous liquid. Immiscible liquids, when left to stand for a period of time will separate into two distinct
layers, one on top of another.
Therefore, immiscible liquids can generally be separated using a separating funnel.

Question 25

What is the atomic number? What does it help find?

Answer 25

The atomic number of an element is the number of protons in each atom, which is also equal to
the number of electrons.

Question 26

What is the mass number? What does it help find?

Answer 26

The mass number is the number of protons plus the neutrons in the nucleus of an atom of the
species concern.

Because the electrons have such small masses compared to a proton or neutron, for
practical purposes, the mass of electrons can be ignored.

Question 27

What is the appearance of a metal and a non-metal?

Answer 27

A metal has a shiny appearance and a non-metal has a dull appearance.

Question 28

What is metal and non-metals state at room temperature (25* C)

Answer 28

Metal would be solid (except for mercury). A non-metal would be mostly gas and some solids.

Question 29

What is metal and non-metals conductivity level?

Answer 29

A metals conductivity level would be high and a non-metal conductivity level is low.

Question 30

What are a metal’s physical properties?

Answer 30

• Malleable which means it can be rolled into sheets.

- Ductile which means it can be pulled into wire.

Question 31

What are non-metals physical properties?

Answer 31

• Brittle
• can shatter easily
• sharp pieces

Question 32

What are the properties of a metalloid?

Answer 32

• Metalloids are glass-like in appearance
• they are semi-conductors
• brittle and are hard solids

Question 33

What is different about Hydrogen?

Answer 33

Hydrogen is a unique element and is not easily classified. Physically, it has properties
similar to non-metals, but chemically it often reacts like a metal.