Salts

Question 1

Solubility of Grp 1, Ammonium, and Nitrates

Answer 1

ALL soluble

Question 2

Solubility of Sulfates

Answer 2

Soluble, except Calcium Sulfate, Lead (II) Sulfate, and Barium Sulfate (C.L.B.)

Question 3

Solubility of Chlorides

Answer 3

Soluble, except Lead (II) Chloride and Silver Chloride (L.S.)

Question 4

Solubility of Carbonates

Answer 4

Insoluble, except Grp 1 Carbonates and Ammonium Carbonate

Question 5

Solubility of Oxides/Hydroxides

Answer 5

Insoluble, except Grp 1 Oxides/Hydroxides, Ammonium Oxide/Hydroxide, Barium Oxide/Hydroxide (B.)
Calcium Oxide/Hydroxide is sparingly soluble

Question 6

Salt

Answer 6

A salt is an ionic compound that is formed when the hydrogen ion (H+) in an acid is replaced by a metal ion or an ammonium (NH4+) ion.

Question 7

Charge 1 Cations

SPSCHA (+)

Answer 7

Sodium ion, Na+
Potassium ion, K+
Silver ion, Ag+
Copper (I) ion, Cu+
Hydrogen ion, H+
Ammonium ion, NH4+

Question 8

Charge 1 Anions

NNCBIHHH (-)

Answer 8

Nitrite, NO2−
Nitrate, NO3−
Chloride, Cl−
Bromide, Br−
Iodide, I−
Hydroxide, OH−
Hydrogen carbonate, HCO3−
Hydrogen sulfate, HSO4−

Question 9

Charge 2 Cations

LCIMCBZ (2+)

Answer 9

Lead (II) ion, Pb2+
Copper (II) ion, Cu2+
Iron (II) ion, Fe2+
Magnesium ion, Mg2+
Calcium ion, Ca2+
Barium ion, Ba2+
Zinc ion, Zn2+

Question 10

Charge 2 Anions

SSSOC (2-)

Answer 10

Sulfite, SO3^2−
Sulfate, SO4^2−
Sulfide, S^2−
Oxide, O^2−
Carbonate, CO3^2−

Question 11

Charge 3 Cations

IA (3+)

Answer 11

Iron (III) ion, Fe^3+
Aluminium ion, Al^3+

Question 12

Charge 3 Anions

PN (3-)

Answer 12

Phosphate, PO4^3−
Nitride, N^3−

Question 13

salt preparation

Answer 13

insol: precipitation (salts)
- 2 aq solns, aq + as -> s

sol grp 1/nh4+: titration (acid + alkali)
- acid + alkali/sol carbonate, aq + aq -> aq

sol gen: rxn of acid w. excess insol substance (acid + excess)
- acid + (etal/insol carbonate)base, aq + s -> aq

Question 14

precipitation - 5

Answer 14

1. mix aq solns tgt to form ppt, stir
2. filter mixture, obtain ppt - residue
3. wash w/ distilled h2o
4. dry w/ filter papers

mix, stir, filter, wash, dry

Question 15

hydrated salts (copper (ii) sulfate)

Answer 15

• many salts combine w/ h2o (water of crystallisation) to form hydrated salts
• hydrated salts can lose water of crystal upon heating to form anhydrous salts
• hydrated & anhydrous hv diff physical properties

anhydrous vs. hydrated copper ii sulfate
1. no water, got water
2. CuSO4, CuSO4.H2O
3. white, blue
4. evaporation to dryness, crystallization

Question 16

define solubility

Answer 16

max amnt of substance that can dissolve in given amnt of solvent at given temp

Question 17

solubility curve & separation techniques

Answer 17

1. steep line/curve - crystallization
2. horizontal line/gentle grad - evaporation to dryness
3. line/curve close to x-axis - filtration

Question 18

crystallisation vs evaporation to dryness

Answer 18

1. CANNOT IF: little change in solubility when temp up, salt decomposes/loses water of crystal upon heating
2. SOLUBILITIES: for mixtures which up w/ temp, for salts which = temp
3. PROCESS: (only step 1 is for evaporation)
   - heat soln until evaporated (dryness)
   - cool to form crystals
   - filter, obtain crystals
   - wash crystals w/ small smnt distilled h2o
   - dry between filter papers