You visited us 1 times! Enjoying our articles? Unlock Full Access!

Byju's Answer

Standard XII

Chemistry

Enthalpy of Solution

The vapours o...

Question

The vapours of organic compound was burnt in oxygen. Equal volume of both gaseous substance were taken at same pressure and temperature. After the reaction, the system was returned to the original condition and it turn out that its volume has not changed. The product of combustion contain 50% $C O_{2}$ (g) and 50% $H_{2} O$ (g) by volume and no other gas. Find the molecular weight of organic compound (in gram/mol) in question.

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is A 30
Let the organic compound be X.

The volume of a gas is directly proportional to the number of moles.

According to the given data, 1 mole of X combines with 1 mole of oxygen to form 1 mole of carbon dioxide and 1 mole of water.

$X + O_{2} \to C O_{2} + H_{2} O$

Thus the molecular formula of X is $C H_{2} O$ .

Its molecular weight is $12 + 2 + 16 = 30$ g/mol

Hence, the correct option is $A$

Suggest Corrections

Similar questions

Q. A gaseous compound having carbon, hydrogen and oxygen was burnt in the presence of oxygen. After combustion, 1 volume of the gaseous compound produces 2 volumes of

C O_{2}

and 2 volumes of steam. Determines the molecular formula of the compound, if all the volumes were measured under the same conditions of pressure and temperature.

Q. 9 volumes of a gaseous mixture contain an organic compound and oxygen sufficient for its combustion. Burning the compound yielded 4 volumes of

C O_{2}

, 6 volumes of

H_{2} O

and 2 volumes of

N_{2}

, find the molecular formula of the compound?

Q. Nine volumes of gaseous mixture consisting of gaseous organic compound A and just sufficient amount of oxygen required for complete combustion yielded on burning

4

volumes of

C O_{2}

6

volumes of water vapours and

2

volumes of

N_{2}

at all volumes measured at the same temperature and pressure. If the compound contains C, H and N only, the molecular formula of the compound A is :

Q. An organic compound

(C_{x} H_{2 y} O_{y})

was burnt with twice the amount of oxygen needed for complete combustion to

C O_{2}

and

H_{2} O

. The hot gases when cooled to

0^{0} C

and

1

atm pressure measured

2.24 L

. The water collected during cooling weighs

0.9

g. The vapour pressure of pure water at

20^{o} C

17.5

mm of Hg and is lowered by

0.104

mm when

50

g of the organic compound is dissolved in

1000

g of water. Give the molecular formula of the organic compound.

0.9

gm of a volatile solid organic compound (molecular weight

= 90

), containing carbon, hydrogen and oxygen, was heated with

224

ml oxygen at

1

atm and

273

K. After combustion, the total volume of gases was

560

ml at

1

atm and

273

K. On treatment with

K O H

, the volume decreased to

112

ml. The formula of the organic compound is

C_{x} H_{y} O_{z}

. Find

(x + y + z) / 2

Join BYJU'S Learning Program