Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Q1 34.5 kg of nitrogen gas (N2) is charged into a metal cylinder at a pressure s

ID: 850395 • Letter: Q

Question

Q1

34.5 kg of nitrogen gas (N2) is charged into a metal cylinder at a pressure such that the gas density is 11.5 kg/m3. How many moles of nitrogen molecules does the cylinder store? The molecular weight of nitrogen atoms is 14.0 and that of hydrogen is 1.0.

Q2

The content of ethyl alcohol in a liquid is 25.0% by weight. A container holds 12.4 kg of the liquid. Find the mass (kg) of ethyl alcohol in the container.

Q3

The mass fraction of benzene in a benzene-toluene mixture is 0.450. What is the mass fraction of toluene in the mixture?

Explanation / Answer

1)

moles=mass of N2/molecular mass

=34.5*1000/28

=1232.142 moles

2)

mass %=25

mass in container= 25/100*12.4

=3.1 kg

3)

mass fraction of toluene = 1- mass fraction of benzene

=1-0.45

=0.55