D And F Block Elements Question 37
Question: Hydrogen is not obtained when zinc reacts with
[CPMT 1994]
Options:
A) Cold water
B) Dilute $ H_2SO_4 $
C) Dilute $ HCl $
D) Hot 20% $ NaOH $
Show Answer
Answer:
Correct Answer: A
Solution:
Zn does not react with cold water.
However it reacts with hot water and yield $ H_2 $
$ Zn+H_2O\xrightarrow{Boil}ZnO+H_2 $
$ Zn+H_2SO_4(dil)\to ZnSO_4+H_2 $
$ Zn+2HCl,(dil)\to ZnCl_2+H_2 $
$ Zn+\underset{20percent}{\mathop{2NaOH}},\xrightarrow{heat}Na_2ZnO_2+H_2 $
BETA
