67. за кривдо розчинності (мал. 6. 3) визначте, яку масу солі можна роз-
чинити в 1 кг води: а) аргентум() нітрату за 0°с; б) натрій нітрату за
20 °c; в) (іі) сульфату за 30°c; г) пломбум(і) хлориду. за 100​

1. I played football yesterday. --> I have played football recently. --> I was playing football yesterday all day long. 2. I worked with my mother at home yesterday. --> I have already worked with my mum. --> I was working with my mom yesterday. 3. I went to the cinema last week. --> I have gone to the cinema recently. --> While I was going to the cinema, my friend broke his leg. 4. I didn't do my homework. --> I haven't done my homework yet. --> I wasn't doing my homework all day long. 5. I made an apple pie one month ago. --> I have already made an apple pie. --> I was making an apple pie when you came home.

4.

а) BaCl₂ + Na₂SO₄ → BaSO₄ + 2NaCl

б) CaO + H₂SO₄ → CaSO₄↓ + H₂O

в) 3AgNO₃ + AlCl₃ → 3AgCl↓ + Al(NO₃)₃

г) Cu(NO₃)₂ + 2NaCl → CuCl₂ + 2NaNO₃

4.

(1)

1) Ca + 2H₂O → Ca(OH)₂ + H₂↑

2) Ca(OH)₂ + CO₂ → CaCO₃↓ + H₂O

3) CaCO₃ + CO₂ + H₂O → Ca(HCO₃)₂

4) Ca(HCO₃)₂ + Ca(OH)₂ → 2CaCO₃↓ + 2H₂O

5) CaCO₃ (t°) → CaO + CO₂↑

(2)

1) 4Al + 3O₂ → 2Al₂O₃

2) Al₂O₃ + 6HCl → 2AlCl₃ + 3H₂O

3) AlCl₃ + 3NaOH → Al(OH)₃↓ + 3NaCl

4) Al(OH)₃ + H₂SO₄ → Al(HSO₄)₃ + 3H₂O

(3)

1) Сu + 4HNO₃ → Cu(NO₃)₂ + 2NO₂↑ + 2H₂O

2) Cu(NO₃)₂ + 2NaOH → Cu(OH)₂↓ + 2NaNO₃

3) Cu(OH)₂ (t°) → CuO + H₂O

4) CuO + H₂SO₄ → CuSO₄↓ + H₂O

5) CuSO₄ + H₂S → CuS↓ + H₂SO₄

(4)

1) 2Zn + O₂ → 2ZnO

2) ZnO + 2HNO₃ → Zn(NO₃)₂ + H₂O

3) Zn(NO₃)₂ + 2KOH → Zn(OH)₂↓ + 2KNO₃

4) Zn(OH)₂ + HNO₃ → ZnOHNO₃ + H₂O

(5)

1) 4К + О₂ → 2К₂О

2) K₂O + H₂SO₄ → K₂SO₄ + H₂O

3) K₂SO₄ + 2NaOH → 2KOH + Na₂SO₄

4) 2KOH + Zn → K₂ZnO₂ + H₂↑

3.

а) K₂O + H₂O → 2KOH

б) 2Al(OH)₃ + 3H₂SO₄ → Al₂(SO₄)₃ + 6H₂O

в) 3BaO + P₂O₅ → Ba₃(PO₄)₂

г) 2Fe(OH)₃ + 3H₂SO₄ → Fe₂(SO₄)₃ + 6H₂O

д) CO₂ + H₂O ⇄ H₂CO₃