Question

3. A mixture of 2.3 g formic acid and 4.5 g oxalic acid is treated with conc. H,SO. The evolved gaseous mixture is passed through KOH pellets. Weight (in g) of the remaining product at STP will be (a) 1.4 (b) 3.0
(c) 2.8 (d) 4.4​

Answer 1

Answer:

2.8

Explanation:

HCOOH

H

2

SO

4

CO+H

2

O .......(i)

(COOH)

2

H

2

SO

4

CO+CO

2

+H

2

O .......(ii)

Conc. H

2

SO

4

is a strong dehydrating agent.

Moles of HCOOH=

46

2.3

=0.05 mole

Moles of (COOH)

2

=

46

2.3

=0.05 mole

From reaction (i),

Number of CO formed =0.05 mole

From reaction (ii),

Number of CO formed =0.05 mole

Number of CO

2

formed =0.05 mole

Hence, total CO formed = 0.05+0.05=0.1 mole

total of CO

2

formed =0.05 mole

KOH pellets absorbs all CO

2

, H

2

O is absorbed by H

2

SO

4

thus CO is remaining product.

Thus, the weight of the remaining product =0.1×28=2.8 g.