Matter

Front 1

Define Matter.

Back 1

Matter is anything that has mass and occupies space.

Front 2

What are physical changes?

Back 2

Physical Changes are changes that are easily reversible and no new substances are formed

Front 3

What are Chemical Changes?

Back 3

Chemical Changes are changes that are not easily reversible and new substances are formed.

Front 4

List 4 examples of physical changes

Back 4

Melting of Ice

Melting of Candle Wax

Change of State of Matter

Magnetization and demagnetization of iron rods

Seperation of mixtures e.t.c

Front 5

List the differences between physical change and chemical change

Back 5

1)Physical changes are easily reversible whie chemical change are not easily reversible.

2)In physical changes, No new substances are formed while chemical changes, new substances are formed.

3)physical changes does not involve any great heat changes except the latent heat changes which occur during changes states, e.g the heat of dissolution and the heat of the latent heats of fusion and vapourization while chemical changes, considerable amount of heat change is usually involved.

4)In physical changes there is no change in the mass of a substance involved in such a change while chemical change, there is a change in the mass of a substance that undergoes such a change.

Front 6

Define an element

Back 6

An element is a substance which cannot be split into simpler units by an ordinary chemical process

Front 7

What are metals and give examples

Back 7

Metals are those metals which ionize by electron loss e.g calcium, magnesium , iron etc

Front 8

What are non-metals and give examples

Back 8

Non-metals are those metals that ionize by element gain e.g chlorine, oxygen, nitrogen, iodine etc

Front 9

What is a Homogeneous Material?

Back 9

A homogeneous material is one which is the same throughout.

Front 10

What are Heterogeneous materials?

Back 10

A heterogeneous material is one which consists of different elements or substances.

Front 11

Difference between the physical properties of metals and non-metals

Back 11

1) Metals are malleable,ductile or sonorous while non-metals, are not malleable,not ductile or not sonorous

2)Metals have great tensile strenght while non-metals, are brittle or soft or not hard

3)Metals are lustrous while non-metals, are non-lustrous

4)Metals are good conductors of heat or electricity while non-metals,they are non-conductors or poor conductors except graphite

5)Metals have high melting point and boiling point while non-metals, except carbon have low melting and boiling point

6)Metals have relatively high density while non-metals,have low density

Front 12

Differences between the chemical properties of metals and non-metals

Back 12

1)Metals are reducing agents or they have tendency to ionize by losing electrons to form cations while non-metals, are oxidizing agents or they tend to ionize by gaining electrons to form anions.

2)Metals form basic oxides with oxygen while non-metals, form acidic oxides with oxygen.

3)Some reactive metals can displace hydrogen from acids while non-metals canmot displace hydrogen from acids.

4)Metals generally tend to form ionic compounds while non-metals generally tend to form covalent compounds.

Front 13

Define compound

Back 13

A compound is a substance which contains two or more elements chemically combined together.

Front 14

Define mixture

Back 14

A mixture contains two or more constituents which can easily be separated by physical methods

Front 15

comparisons of mixture and compounds

Back 15

1) mixture may be homogeneous or heterogeneous while compound,is always homogeneous

2)mixture constituents are not chemically bound together and can,therefore,be easily separated and recovered by physical means while compound,component elements are chemically bound together and cannot be separated by physical means

3)mixture constituents can be added together in any ratio by mass.hence, a mixture cannot be represented by a chemical formula while compound,components are present in a fixed ratio by mass. Hence, a compound can always be represented by a chemical formula.

4)mixture properties are the sum of those of its individual constistuents while compound,properties differ entirely from those of its component elements.