Question icon
Grade 12Physical Chemistry

The decomposition of a certain mass of CaCO3 gave 11.2 dm3 of CO2 gas at STP. The mass of KOH required to completely neutralise the gas is (A) 56 g (B) 28 g (C) 42 g (D) 20 g

Profile image of saurabh kumar
12 Years agoGrade 12
Answers icon

2 Answers

Profile image of R Shyam Sundar
6 Years ago
For complete neutralisation,
2KOH+CO2 gives K2CO3 + H2O
For 11.2dm^3 i.e.,11.2L(half mole) we need 1mole KOH.
So weight of KOH is 56g
 
Profile image of Vikas TU
6 Years ago
Dear student 
Weight of 11.2 dm^3 of CO2 gas at STP = 44/2 = 22 gram 
KOH + CO2 -> KHCO3 
KOH required = 56/44  * 22 = 28 gram 
B is correct ans.
Hope this helps 
Good Luck