Может ли реакция обмена идти между двумя нерастворимыми веществами и почему?

ответ:

3.

1) no we aren`t

2) yes he does

3)yes she has

4) no i don`t

5)no it hasen`t

6) yes they are

объяснение:

1) are we friends? no, we aren`t

2) does petros have a close friends? yes, petros have a close friends

3)has she got the cat? yes, she has got the cat

4)do you have a sister? no, i haven`t

5) has it got a name? no it hasn`t

1) 2hno3 + cu(oh)2 = cu(no3)2 + 2h2o;

2h + 2no3 + cu(oh)2 = cu + 2no3 + 2h2o;

2h + cu(oh)2 = cu + 2hno3

2) 6hno3 + fe2o3 = 2fe(no3)3 + 3h2o;

6h + 6no3 + 2fe + 3o = 2fe + 6no3 + 3h2o;

6h + 3o = 3h2o

3) 2hno3 + na2co3 = 2nano3 + h2co3(сразу разлагается на h2o и co2);

2h + 2no3 + 2na + co3 = 2na + 2no3 + h2o + co2;

2h + co3 = h2o + co2

4al + 3o2 = 2al2o3 (t)

2al2o3 + 6hcl = 2alcl3 + 3h2o

alcl3 + 3naoh = al(oh)3 + 3nacl

2al(oh)3 =  al2o3 + 3h2o  (t)

2al2o3 = 4al + 3o2  (электролиз)