A 5.00-L gas sample at 100.°C and 640. torr contains 20.3% neon and 79.7% xenon by mass. What are the partial pressures of the individual gases?

The answers to the question are

Partial pressure of neon = 399.42

Partial pressure of xenon = 240 torr

Explanation:

From the universal gas equation

P×V = n × R × T

n = P × V÷(R×T)

= ((640 torr /(7.5×10^(-3))× 5/ L)÷(8.314×373.15))/1000

= 0.13751 moles

Therefore, if the mass of gas = x, we have

0.203×x mass of neon and

0.797×x mass of xenon

Molar mass of neon = 20.179 g/mol

Molar mass of xenon = 131.30 g/mol

Summing the moles of neon and xenon, we have

(0.203×x)/ (20.179) + 0.797×x/( 131.30) = 0.13751 moles

1.6×10^(-2)x= 0.13751

x = 8.5306 g

Number of moles of neon =

(0.203× 8.5306 )/ (20.179) = 8.58×10(-2) moles

Mole fraction of neon = (8.58×10(-2))/ 0.13751 = 0.624

Partial pressure of neon = (mole fraction)×(total pressure of gas) = 0.624× 640 torr = 399.42 torr

Partial pressure of xenon = 240 torr

a. hope i'm right

explanation:

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6