A mixture of 2.3 g formic acid and 4.5 g oxalic acid is treated with conc. `H_2 SO_(4)`. The evolved gaseous mixture is passed through KOH pellets. Weight (in g) of the remaining product at STP will be

Options

A. `1.4`
B. `3.0`
C. `2.8`
D. `4.4`

Answer

C

Explanation

`H_2 O` is absorbed by `H_2 SO_4`. Gaseous mixture (containing CO and `CO_2`) when passed through KOH pellets, `CO_2` gets absorbed. Moles of CO left (unabsorbed) = ` 1/20 +1/20 =1/10`
Mas of CO = moles ` xx ` molar mass `=1/10xx 25 = 2.8 g `