1.6 The Periodic table

Name of group 0

Noble gases

Chemical properties of Group 0

Inert (very unreactive)

Electron structure of group 0

All have full shells of electrons and are therefore very stable

Physical properties of group 0

all colourless gasses at room temperature

Pattern in boiling point down group 0

Boiling point increases down the group

Monatomic

Made only of single atoms

Chemical structure of group 0

monatomic

Transition elements are found

In the middle block of the periodic table

Physical properties of transition elements

Hard, high melting points, strong and dense

Chemical properties of transition elements

Slow/no reaction with oxygen, water and halogens

Charges on transition metal ions

Form positive ions often with the ability to form more than one ion

Iron ions

Fe2+, Fe3+

Catalyst

A substance that speeds up the rate of a chemical reaction without being used up

Transition metals are good catalysts because

They form more than one ion

Iron catalyses

The haber process

Colours of transition metal compounds

Coloured solids and solutions

Reactivity of transition elements

Less reactive than group 1+2 metals

Corrosion

The gradual wearing away of a metal element due to a chemical reaction

Rust

The corrosion of iron

Colour Copper (ii) oxide

Black

Colour Copper (ii) carbonate

Green

Colour hydrated Copper (ii) sulfate

Blue

Colour Copper (ii) ions in solution

Blue

Name of Group 7 elements

The halogens

Group 7 elements have similar chemical properties

because they all have 7 outer shell electrons

Diatomic molecule

A molecule consisting of two atoms

Chemical structure of group 7

Diatomic molecules

Pattern in melting points and boiling points down group 7

Melting and boiling points decrease

Pattern of reactivity down the halogens

They get less reactive

Reason for patterns in reactivity

larger atomic radius, more shielding, less nuclear attraction, harder to gain a reaction

Group 7 elements react by

gaining 1 electron

Displacement reaction

A reaction in which a more reactive element replaces a similar element in a compound

Potassium bromide + Chlorine -->

Potassium chloride + Bromine

Sodium chloride + Bromine -->

No reaction

Sodium iodide + Bromine -->

Sodium bromide + Iodine

Name for Group 1 elements

Alkali metals

Pattern in reactivity down group 1

Reactivity increases

Density of group 1

low density, which decreases down group 1

Conductivity of group 1

good conductors of heat and electricity

Appearance of group 1 elements

shiny when cut, but tarnish as they react with oxygen

Colour of group 1 compounds

White solids/colourless solutions

Metal + water -->

metal hydroxide + hydrogen

Observations: Sodium + Water

Floats on surface, melts into a bowl, fizzes, moves on the surface of the water

Observations: Sodium + chlorine

Burns with a yellow flame, producing a white compound

Observations: Lithium + water

Floats on the surface of the water, moves around and fizzes

Observations: Potassium + water

Floats on the surface of the water, moves around, fizzes, melts into a ball, burns with a lilac flame.

When group 1 elements react

they lose their outer electron

Potassium is more reactive than sodium because

atomic radius increases, shielding increases, nuclear attraction decreases, easier to lose an electron

Metals

Elements which form positive ions

Non-metals

Elements which do not form positive ions

Metals position on periodic table

on the left hand side

Non-metals position on periodic table

on the right hand side

Physical properties of metals

Shiny, malleable, ductile, sonorous, good conductors of heat and electricity

Physical properties of non-metals

Dull, brittle, insulators of heat and electricty, liquids and gases at room temperature

Malleable

easy to shape or bend

Ductile

Easily stretched into a wire

Good conductor of heat

Allows heat energy to travel through with ease

Good conductor of electricity

Allows electrical current to flow through with ease

Sonorous

Producing a deep or full sound

Brittle

Easily broken

Insulator of heat

a material that does not allow heat to pass through easily

Insulator of electricity

a material that does not allow electric current to pass through easily

pH of metal oxides

Acidic

pH of non-metal oxides

Basic

atomic number

the number of protons in the nucleus of an atom

atomic mass

The average mass of all the isotopes of an element

mass number

the sum of the number of neutrons and protons in an atomic nucleus

Order of elements on historic periodic table

Elements were ordered by atomic weight

Order of elements on modern periodic table

Elements are ordered by atomic number

Dmitri Mendeleev's ideas

Ordered elements by atomic weight BUT changed the order/left gaps to keep elements with similar properties in the same collumn

Advantages of Mendeleev's ideas

He was able to predict the properties of elements in the gaps.

Group

A vertical column of elements with the same number of outer shell electrons

Period

A horizontal row of elements with the same number of electron shells

Physical properties

observed or measured characteristics of a substance

Chemical properties

How a substance reacts with other substances.

Groups missing from Mendeleev's periodic table

Transition metal, Lanthanides, Actinoids

colours of halogens

fluorine is pale yellow

chlorine is green-yellow

bromine is red-brown

iodine is blue-black