chemistry
posted by eng .
1)
14 moles of Ar
12 moles of N2
2 moles of BF3
If the total number of mol present in the mixture visualized is 1.43, calculate the number of mol of N2.
2)
11 moles of N2
4 moles of CSH4
If the total number of mol present in the mixture visualized is 1.68, calculate the number of mol of N2

I am not exactly sure of what is given.
1) if the mixture is 14 parts Ar, 12 parts N2, and 2 parts BF3, then
molesN2=1.43*12/28 moles 
thats right