1. take 6 test-tubes and a holder, 0.1M solutions of K/Na halides into beakers
2. add every halide to 2 tubes, to half add ammonia and note colour.
3. leave other half for sunlight for 1hour
2. 1. Moisten stips of filterpaper with lead(II) ethanoate and potassium dicromate.(just put them ready)
2. Take now solid halide salts and put 0.1g (fills round bit) to 12 test-tubes, add H2SO4 and warm if necessary.
3. Add 10drops of conc. H2SO4 and test with moistened filter paper
4. Add 10drops of conc. H3PO4 and test with moistened filter paper.
3. 1. collect the gas into apparatus as in fig. p115 (dry testtubes, solid phosphoric)
Use 6 testtubes, bunsen to warm, 2g of halide and phosphoric and corks to prevent escaping.
Invert a tube in water and remove cork to
observe solubility. Residue is air.
Take a glass rod dipped into conc. ammonia and hold near the mouth of test-tube
Heath the end of nicrome wire or glass rod and put into the gas.
Operation |
Cl- |
Br- |
I- |
Observation |
Equation |
Add AgNO3 |
white ppt |
cream ppt |
yellow pt |
precipit |
Ag+AgH(s) |
add ammonia |
soluble |
soso |
not |
prec.disappears |
NH4Ha(aq/s) |
Leave AgHal to sunlight |
purplgrey |
greenyelo |
no |
colourchange |
Ag(s)+H(g) |
When conc.H2SO4 is added |
HCl |
SO2 Br2 |
SO2 Br2 |
H2SO4 reducer |
H H2O SO2 |
test with lead(II) ethanoate |
white ppt |
yellow pt |
no(yellow |
ppt |
PbCl2(s) |
test with potassium dicromate |
no |reduced due to SO2 |
||||
When conc.H3PO4 is added |
HCl |
HBr |
HBr |
H3PO4 not redu |
Na3PO4 |
test with lead(II) ethanoate |
white |
yellow |
yellow |
||
test with potassium dicromate |
no |
||||
colour of halide |
yellow |
yellow |
pink |
||
solubility in water |
yes |
soso |
no |
||
reaction with ammonia |
white gas |
yellow ga |
yellow ga |
reacts |
NH4Hal(s) |
Reaction of heath |