a reactive metal

b unreactive gas

Give 5 properties of the alkali metals

1. They are soft - can be cut easily with a knife

2. They are very reactive

3. They are not very dense - they float on water

4. They have one electron in their outer shell

5. They react with water

shells

orbits

Protons (+)

Neutrons (no charge)

a neutral

b no

complete the table

Energy levels        max. number of electrons

 1                             ^a......

2                             ^b......

3                             ^c......

4                             ^d......

a 2

b 8

c 8

d the rest

How do the alkali metals try to get more stable?

What happens when lithium (Li) is dropped into water?

It floats, fizzes gently and dissapears as it turns into Lithium hydroxide (LiOH). It makes an alkali solution as it dissolves. It also gives off hydrogen gas.

The reaction gives out enough energy to melt the sodium, it skates around the surface. More vigorous than lithium.

Also produces sodium hydroxide (NaOH) and hydrogen.

It floats and ignites with a lilac flame.

Also produces potassium hydroxide (KOH) and hydrogen.

No, they must be dissloved first.

When light given off by a flame is split into a spectrum, single pure colours can be seen.

Each element gives a unique flame spectra.

It's due to the electrons. The heat gives them energy, they move up to higher energy levels. They then lose energy and fall to a lower energy level. They give out energy in the form of light.

Each atom has a different combination of "jumps", e.g. Hydrogen has 3 lines - 3 combinations of "jumps"

What is each line on a spectra?

No, mass before = mass after

The iron wool must be heated initially, but one the reaction has started, heat from it keeps it going.

There is an instant, vigorous reaction. Clouds of iron chloride form. Little iron is left.

Strong heat is needed for a reaction. It's slow to react and only a small amount does react. Iron iodite is formed.

Put the following in order of reactivity (most to least):

Bromine (Br₂)

Iodine (I₂)

Chlorine (Cl₂)

Chlorine (Cl₂)

Bromine (Br₂)

Iodine (I₂)

1. Dense, pale gas

2. Smelly and poisenous

3. occurs as chlorides, esp. sodium chloride in the sea

1. Deep red liquid with red-brown vapour

2. Smelly and poisenous

3. Occurs as bromides, esp. magnesium bromide in the sea

1. Grey solid with purple vapour

2. Smelly and poisenous

3. Occurs as iodides and iodites in some rocks and in seaweed

What happens when:

       melt

Na⁺ Cl^- ----------->

         disolve

Na⁺          Cl^-

^{+ ion               -ion} 

^{Cation                 Anion}

At Cathode:

Na⁺   +   e^-   -------->

At Anode

Cl^-   -------->

Cl + e^-