Answer:
H₂: 0.48, N₂: 0.43; Ar: 0.09
Explanation:
First of all, sum all the pressures to know the total pressure in the mixture.
434 Torr + 389.9 Torr + 77.9 Torr = 901.8 Torr
Mole fraction = Pressure gas / Total Pressure
Mole Fraction H₂: 434 Torr /901.8 Torr = 0.48
Mole Fraction N₂: 389.9 /901.8 Torr =0.43
Mole Fraction Ar: 77.9 /901.8 Torr = 0.09
Remember: <u>SUM OF MOLE FRACTION = 1</u>
The correct Answer based on my calculations is C
I think the correct answers are X2Y and X3Y, X2Y5 and X3Y5, and X4Y2 and X3Y,
for the following reason:
If you look at the combining masses of X and Y in
each of the two compounds,
The first compound contains 0.25g of X combined with
0.75g of Y
so the ratio (by mass) of X to Y = 1 : 3
The second compound contains 0.33 g of X combined with
0.67 g of Y
so the ratio (by mass) of X to Y = 1 : 2
Now, you suppose to prepare each of these two
compounds, starting with the same fixed mass of element Y ( I will choose 12g
of Y for an easy calculation!)
The first compound will then contain 4g of X and 12g
of Y
The second compound will then contain 6g of X and
12g of Y
<span>The ratio which combined
the masses of X and the fixed mass (12g) of Y
= 4 : 6
<span>or 2 : 3 </span>
So, the ratio of MOLES of X which combined with the
fixed amount of Y in the two compounds is also = 2 : 3 </span>
The two compounds given with the plausible formula must therefore contain
the same ratio.
