Question

In the chemical reaction,
$K_2{Cr}_2{O}_7+{aH}_2{SO}_4+{bSO}_2\to K_2{SO}_4+{Cr}_2{(SO}_4{)}_3+{cH}_{2}O$. a, b and c are:

• A. 1, 3, 1
• B. 4, 1, 4
• C. 3, 2, 3
• D. 2, 1, 2

Answer 1

Answer: (A)

1, 3, 1

It is balancing of reaction.

Balancing Hydrogen atoms on both sides $\Rightarrow 2\left(a\right)=2\left(c\right)\Rightarrow a=c$

Balancing Sulphur atoms on both sides $\Rightarrow a+b=1+3\Rightarrow a+b=4$

Balancing Oxygen atoms on both sides $\Rightarrow 7+4a+2b=4+12+c$

$\Rightarrow 7+4a+2(4-a)=16+a$

On solving we get, $a=1$

$a=c=1$,

$a+b=4$

$⟹1+b=4$

$⟹b=3$

So,

$a=1,b=3$ and $c=1$