Question

The vapour density of a mixture of NO2 and N2O4 is 38.3 at 26.7oC. Calculate the number of moles of NO2 in 100 g of the mixture.

Solution

Correct option is

0.437

 

Suppose NO2 present in 100 g of the mixture = g

Then N2O4 present in the mixture = (100 – x)g

Molar mass of NO2 = 14 + 32 = 46 g mol–1

Molar mass of N2O4 = 92 g mol–1

Molar mass of mixture 

Expressing all quantities in terms of moles, we should have

                    

or  92 + 4600 – 46= 5524.8

or 46x = 924.8

or     x = 20.1 g

SIMILAR QUESTIONS

Q1

A black dot used as a full stop at the end of a sentence has a mass of about one attogram. Assuming that the dot is made up of carbon, calculate the approximate number of carbon atoms presents in the dot?  

Q2

Insulin contains 3.4% sulphur. Calculate the minimum molecular mass of insulin.

Q3

 atoms of iron weigh as much as 1cc of H2 at S.T.P. What is the atomic mass of iron?

Q4

4 g carbon were heated with 8 g of sulphur. How much carbon disulphide (CS2) will be formed when the reaction is completed? What will be its percentage purity?  

Q5

How many years would it take to spend Avogadro’s number of rupees at the rate of 10 lakh rupees per second?

Q6

Gastric juice contains about 3.0 g of HCl per litre. If a person produces about 2.5litre of gastric juice per day, how many antacid tablets each  containing 400 mg of Al(OH)­3 are needed to neutralize all the HCl produced in one day. 

Q7

What volume at N.T.P of ammonia gas will be required to be passed into 30mL of N H2SO4 solution to bring down the acid normality to 0.2 N?

Q8

 

The mass of one litre sample of ozonised oxygen at N.T.P was found to be 1.5 g. when 100mL of this mixture at N.T.P were treated with turpentine oil, the volume was reduced to 90mL

Calculated the molecular mass of ozone. 

Q9

7.4 gram of a metal hydroxide on heating gives 5.6 g of metal oxide. Calculate the equivalent weight of the metal.

Q10

How many molecules are there in 10 litres of gas at a pressure of 75 cm at 27 degree Celsius?