A balloon filled with 2l of hydrogen gas contains 0.18 g of H2.?

Question

A balloon filled with 2l of hydrogen gas contains 0.18 g of H2.

(a) How many mol of H2 are there in the balloon ?
(b) How many molecules does it contain ?
(c) How many atom does it contain ?

DATA NA = 6.023 x 1023 mol 1
Please help me:0(

Answer 1

Molecular weight H2 = 2.016 g/mol
(a) 0.18 g / 2.016 = 0.0893 mole of H2
(b) 0.0893 x 6.02 x 10^23 = 5.37 x 10^22 molecules
(c) Since in one molecule of H2 there are 2 atoms we get :
5.37 x 10^22 x 2 = 1.07 x 10^23 atoms

Answer 2

a) 1 mole of H2 has a mass of 2*1=2g
so 0.18g correspond to 0.18/2= 0.09 mole

b) 1 mole=6.023*10^23 molecule so
0.09*6.023*10^23 =5.42*10^22 molecule

c) 1 molecule has 2 atoms so
number of atoms = 5.42*10^22*2 =1.084 * 10^23 atoms

Answer 3

a)0.09 mol of H2
b)?
c)?

No. of moles= Mass of H2/ Mr of H2
= 0.18/ 2
= 0.09 mol

As for molecules and atoms, im not so sure...

Answer 4

This question is incomplete, temperature and pressure are needed for the question to be complete.


following data is from wikipedia
Density (0 °C, 101.325 kPa)
0.08988 g/L

answer = 2 x 0.08988
=0.179 g at 0 °C & 101.325 kPa.