Answers

2015-08-11T20:43:02+05:30

This Is a Certified Answer

×
Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
Mass number of helium=4
1 mole of helium gas is present in 4 g of helium gas
1 gm of helium gas contains 1÷4 moles of helium
0.49gm contains 0.49÷4 moles of helium
=0.1225 moles
0
2015-08-14T18:16:24+05:30
The formula for calculating number of moles is as follows:
no.moles= mass/molar mass
mass of helium is 0.49 g
molar mass of helium is 4 g/mol
moles of He= 0.49g/4g/mol
=0.1225 mol.
Therefore, the no.of moles of helium is 0.1225 mol
0