RP 11 - inorganic

what is RP 11

carry out simple test tube reactions to identify transition metal ions in aqueous solution

test 1a - NaOH

1. place 10 drops solution in test tube

2. add NaOH, shake gently, dropwise until in XS

3. record observations

test 1b

1. half fill 250cm3 beaker with freshly boiled water

2. allow four test tubes containing mixtures from 1a to stand in it for 10 mins

3. record observations

test 2 - Na2CO3

1. place 10 drops Na2CO3 in test tube

2. add 10 drops solution and shake gently

3. record observations

test 3 - AgNO3

1. add 10 drops solution in test tube

2. add 10 drops AgNO3 and shake gently

3. allow four test tubes to stand for 10 mins

4. record observations

results

what can happen when Fe2+ is left to stand

it becomes oxidised by oxygen in the air

• turns brown at the surface

whats more stable and why Fe2+ or Fe3+

Fe3+ because they have a half filled d subshell

an assumption made when identifying transition metal ions using precipitation reactions and explain why this assumption is important

• assumption - the reagent used is pure and uncontaminated

• explanation - ensures any ppt formed is due to the intended reagent-ion reaction