The decomposition of a certain mass of `CaCO_(3)` gave 11.2 `dm^(3)` of `CO_(2)` gas at STP. The mass of KOH required to completely neutralise the gas is:

Options

A. 56g
B. 28g
C. 42g
D. 20g

Answer

B

Explanation

`11.2dm^(3)` of `CO_(2)` at `STP=(1)/(2)"mole"CO_(2)`
`KOH+CO_(2)rarrKHCO_(3)`
`(1)/(2)` mole `CO_(2)` will be neutralised by `(1)/(2)` mole KOH,i.e.,28g KOH