Question

Assertion: Aluminium and zinc metal evolve $H_2$ gas from $NaOH$ solution
Reason: Several non-metals such as $P,S,Cl$ etc. yield a water and other compounds instead of $H_2$ gas from $NaOH$.

• A. Both Assertion and Reason are correct and the Reason is the correct explanation of Assertion
• B. The Assertion is correct but the Reason is incorrect
• C. Both Assertion and Reason are correct but the reason is not the correct explanation of Assertion
• D. The Assertion is incorrect but the Reason is correct

Answer 1

Answer: (C)

$Zn+2NaOH\to N{a}_{2}Zn{O}_2+H_2$
$2Al+2NaOH+2H_{2}O\to 2NaAl{O}_2+3H_2$
So Assertion (A) is correct.
$P_4+3NaOH+3H_{2}O\to 3Na{H}_{2}P{O}_2+P{H}_3$
$4S+6NaOH\to N{a}_2{S}_2{O}_3+2N{a}_{2}S+3H_{2}O$
$C{l}_2+2NaOH\to NaCl+NaClO+H_{2}O$
This reaction of $C{l}_2$ is with cold and dilute $NaOH$.
$3C{l}_2+6NaOH\to 5NaCl+NaCl{O}_3+3H_{2}O$
This reaction of $C{l}_2$ is with hot and conc. $NaOH$.