A sample of neon effuses from a container in 73 seconds. The same amount of an unknown noble gas requires 149 seconds.

Question

Identify the gas.

Answer 1

Use Graham's law of effusion.

rateX/rateNe= sqrt (molmassNe/molmassx)

solve for mole mass of x.

Now notice this: rate above is volume/time

You are given time. So if you want to plug in the given times, the equation becomes

time1/timeNe=sqrt(molmass1/timeNe)

Answer 2

i am not doing it right , first i got Hydrogen and then Helium...im not sure what im doing wrong

Answer 3

149/73= sqrt(molmassX/20.18)
molmassX=4.16*20.18

The closest Nobel element is Radon.

Answer 4

The closest would be Krypton, not Radon

Answer 5

wouldnt the equation be 149/73=sqrt(20.18/molar massx)

Answer 6

No it is inverse

Answer 7

How did you get the 4.16?

Answer 8

149 Ne/73 unknown = sqrt(MM unknown/20.183)
Square root the denominator

2.0411 = sqrt(MM unknown)/ 4.4925
multiply the denominator to isolate the unknown

2.0411 x 4.4925 = sqrt(MM unknown)

9.16972 = sqrt(MM)
Square both sides,

84.083 = unknown molar mass, closest element is the noble gas Radon.

Answer 9

Bleh, I meant Krypton, not Radon.