[matx132]

Welcome,
At the start i sorry for my english but this is not my first language

In School we have exercises with chemistry and i have trouble with some exercises,
few i done but i don't know is correct.

Here are some exercises:

Zn + H₂SO₄  i think this is good -> ZnSO₄ + H2O
Pb + 2H₂SO₄ i think this is good -> PbSO₄  + SO₂ + H₂O
Cu + H₂SO₄ i think this is good -> CuSO₄ +  SO₂ + H₂O
Fe + H₂SO₄ i think this is good -> FeSO₄ + H₂

and instead H₂SO₄ it is HNO₃,HCl

but i don't know is all correct and how do the rest(other)

And that the concentrated solutions

HNO₃ with Al,Cu
HCl (cs) with Al,Cu

Please help me and write how i must do other because I have yet to understand this.

Best Regards,
Matx132

[rabolisk]

Concentrated nitric acid is an oxidizing agent, whereas HCl is not. That should be enough to predict the reactions.

[matx132]

are you suggest when NO₂ is concentrated with e.g.  Cu :
Cu + 4HNO₃ --> Cu(NO₃)₂ + 2NO₂ + 2H₂O
and with Al:
Al + 2HNO₃ --> AlNO₃ + NO₂ + H₂O
?
and when i write "i think is good" is all correct?

Thanks for help

[rabolisk]

It's hard to tell, because lead may be resistant to the oxidation by sulfuric acid. It may be better to represent lead as you did iron.

Also, to be sure, some metals react with HCl, just not in the same fashion as nitric acid. (i.e. Cl^- is very different from NO3^-)