Q13-126CP

Question

Three gaseous mixtures of N2(blue), Cl2(green), and Ne (purple) are depicted below.

  1. Which has the smallest mole fraction of N2?
  2. Which have the same mole fraction of Ne?
  3. Rank all three in order of increasing mole fraction of Cl2.

 

 

Step-by-Step Solution

Verified
Answer
  1. Solution C has the smallest mole fraction of N2.
  2. Solution A and solution C have the same mole fractions of Ne.
  3. the order of increasing mole fraction of Clis as χB<χA<χC.

 

1Step 1: Mole fraction

Mole fraction is the ratio of the number of moles of one component of a solution or other mixture to the total number of moles representing all the components. It can be calculated as follow;

 molefraction=(molesofonecomponent)(totalmoles)

2Step 2: Smallest mole fraction of N 2

(a)

 For solution A:

Moles of nitrogen = 3mol 

Total moles present in solution=3molN2+3molCl2+2molNe=8mol  

Mole fraction of Ncan be calculated as

 XA=moles of nitrogentotal moles=3mol8mol=0.375

For solution B:

Moles of nitrogen =4mol

Total moles present in solution=4molN2+2molCl2+4molNe=10moles

Mole fraction of Ncan be calculated as

  XB=moles of nitrogentotal moles=4mol10mol=0.4

For solution C:

Moles of nitrogen = 4mol

Total moles present in solution=4molN2+5molCl2+3molNe=12moles

Mole fraction of can be calculated as

XC=moles of nitrogentotal moles=4mol12mol=0.333

Hence, from the above calculations it is clear that solution C has the smallest mole fraction of N2

3Step 2: Smallest mole fraction of Ne

(b)

 For solution A:

Moles of Ne =2mol

Total moles present in solution =3molN2+3molCl2+2molNe=8mol

Mole fraction of Ne can be calculated as

 XA=moles of Netotal moles=2mol8mol=0.25

For solution B:

Moles of Ne = 4mol

Total moles present in solution=4molN2+2molCl2+4molNe=10moles

Mole fraction of Ne can be calculated as

 XB=moles of Netotal moles=4mol10mol=0.4

For solution C:

Moles of Ne=3mol

Total moles present in solution=4molN2+5molCl2+3molNe=12moles

Mole fraction of Ne can be calculated as

XC=moles of Netotal moles=3mol12mol=0.25

So, from the above calculation it is clear that solution A and solution C have the same mole fractions of Ne.

4Step 3: order of increasing mole fraction of Cl 2

(c)

 For solution A:

Moles of Cl2=3mol

Total moles present in solution =3molN2+3molCl2+2molNe=8mol

Mole fraction of Clcan be calculated as

 XA=moles of Cl2total moles=3mol8mol=0.375

For solution B:

Moles of Cl=2mol

Total moles present in solution=4molN2+2molCl2+4molNe=10moles

Mole fraction of Clcan be calculated as

 XB=moles of Cl2total moles=2mol10mol=0.2

For solution C:

Moles of Cl2=5mol

Total moles present in solution=4molN2+5molCl2+3molNe=12moles

Mole fraction of Clcan be calculated as

 XC=moles of Cl2total moles=5mol12mol=0.42

From the above calculation the order of increasing mole fraction of Clis as χB<χA<χC.