Question

24
2
The following observations were made by a student on treating four metals P,
Q, R and S with the given salt solutions:
Sample MgSO4(aq)
Zn(NO3)2(aq) CaSO4(aq)
Na2SO4(aq)
P
No reaction
Reaction
Reaction
No reaction
occurs
occurs
Q
Reaction
Reaction
Reaction
Reaction
occurs
occurs
occurs
occurs
R
No Reaction
No Reaction
No Reaction
Reaction
Occurs
S
No Reaction
No Reaction
No Reaction
No Reaction
Based on the above observations:
(a) Arrange the given samples in the increasing order of reactivity
(b) Write the chemical formulae of products formed when Q reacts with
CuSO4 solution
25.​

Answer 1

Answer:

(i) In increasing order

S<R<P<Q (S have least reactivity and Q had the most)

(ii) CuSO₄ + Q → Cu + QSO₄

Explanation:

If it is the Question 24 of Science Sample Paper 2020 then the above answer is applicable.

Here simply first write the Reactivity series is

i.e. K, Na, Ca, Mg, Al, Zn, Fe, Pb, H, C, Hg, Au, Ag, Pl

as the metal solution

Na₂SO₄ will show reaction if a metal of high reactivity then Na reacts with it.

Similarly,  CaSO₄ will show reaction if a metal of high reactivity then Ca reacts with it.

Similarly,  MgSO₄ will show reaction if a metal of high reactivity then Mg reacts with it.

Similarly,  Zn(NO₃)₂ will show reaction if a metal of high reactivity then Zn reacts with it.

thus  as  

Q replace all metals from their salt solution therefore it has the highest reactivity.

followed by P that displaced Ca and Zn from its salt solution.

followed by R that displaced only Zinc from its salt solution.

and finally S has the least reactivity therefore it didn't replace any metal from their salt solution.

Therfore in Increasing order

S<R<P<Q

(II) As Q is the most reactive and it displaces even Na from its salt solution so it will surely replace Cu as it is less reactive than Na.

Therefore

CuSO₄ + Q → QSO₄ + Cu

Here as no valency is given the product may be even Q₂SO₄ and so on....

Hope it helps........ ;-)  

Answer 2

Answer

S < R < P < Q

HOPE IT HELPS... ❤