General overview (groups in the periodic table)

Properties of alkali metals

Soft, relatively low melting points

Reaction of lithium in water

Fizzes steadily, dissolves

Reaction of sodium in water

Melts to form a ball, fizzes rapidly, becomes smaller ball until it dissolves

Reaction of potassium in water

Quickly melts to form a ball, burns violently with sparks and a lilac flame, disappears rapidly, small explosion

What is the pattern of reactivity in alkali metals?

Reactivity increases going down the group

What is another name for the alkali metals?

Group 1

How does electron configuration relate to reactivity of group 1?

Atoms become larger, so the outer electron is further from the nucleus. The force of attraction between the nucleus and the outer electron decreases, so the outer electron is more easily lost

What colour is chlorine?

Pale green

What colour is bromine?

Brown

What colour is iodine?

Blue-black

What is the pattern in physical properties of halogens?

Low melting and boiling points

What is another name for halogens?

Group 7

What is the test for chlorine?

Damp litmus paper will be bleached white in the presence of chlorine

What happens when halogens react with metals?

They form metal halides

What can hydrogen halides do?

Dissolve in water to form acidic solutions

What is the pattern of reactivity in halogens?

They become less reactive down the group

Why are displacement reactions redox reactions?

Electrons are lost or gained by reactants

How does electron configuration relate to reactivity of group 7?

The molecules become larger, and the force of attraction between the nucleus and the outermost shell of electrons is weak, meaning it is harder to keep hold of new electrons

Why are the noble gases inert?

They have full outer shells

What is the pattern in physical properties of noble gases?

Density increases going down the group, but boiling points increase going up the group

How do the uses of noble gases depend on inertness?

They are used to not react with anything and damage the product

How do the uses of noble gases depend on low density?

It allows things to be lighter than air

How do the uses of noble gases depend on non-flammability?

They prevent object from being set on fire

What is another name for noble gases?

Group 8