Iron displaces copper from its salt solution because:

Q. Iron can liberate $H_2$ from dil. $H_2{SO}_4$ but copper cannot liberate $H_2$ from dil. $H_2{SO}_4$.
Why?

Q. Which of the following is the correct conclusion. Also, give the reason?

Observation	I	II	III
Solution after reaction	Colourless	Colourless	Colourless
Metal Deposited	Zn	Cu	Fe

(a) Al is more reactive than Cu and Fe but less reactive than Zn
(b) Al is more reactive than Cu but less reactive than Zn and Fe
(c) Al is more reactive than Zn and Cu but less reactive than Fe
(d) Al is more reactive than Zn, Cu, Fe.

Q. Metal A dipped in a salt of metal B displaces B from the solution. This shows that
(a) A is more reactive than B.
(b) B is more reactive than A.
(c) both A and B are equally reactive.
(d) no such conclusion can be drawn.

Q.

The given reaction indicates that:

Cu + 2AgNO₃ → Cu(NO₃)₂ + 2Ag

Q. Given two test tubes, A and B, A is CuSO${}_4$ solution (blue) and B is FeSO${}_4$ solution (green). When few iron nails are dipped in both the solutions, it is observed that the colour of solution A changes to green but the colour of solution B remains the same. This is because:

(More than one option can be correct)