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

Options

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

Answer

A

Explanation

`{:(2KOH,+,CO_(2)rarrK_(2)CO_(3)+H_(2)O),(2(39+16+1),,22.4dm^(3)),(=112g,,"at STP"):}`
22.4 `dm^(3)` of `CO_(2)` at STP required KOH = 112 g
`therefore 11.2dm^(3)` of `CO_(2)` at sTP will required KOH
= 56 g