Question

A chemist was asked to find the molecular weight of a gas and found that 3.73 g of the gas occupied 300 cm^3 at 25 celsius and 92.4 kpa. what is the molecular weight?

Answer 1

ideal gas law

Answer 2

you got the pressure as in kpa and the temperature in Centigrade and convert the volume of cm3 into m3.... and apply these three values in gas law equation...as

PV = nRT....
n=PV/RT
you can get the R value from internet.... then you will get n value...
which is no. of moles.... so.. 1 mole = weight/ molecular weight....
so divide the given wight of sample with n value... you will get the mol. wt.

Answer 3

connect 2 formulas
Mole= mass/Mr
PV= nRT
n is mole
so if we connect these 2 formulas we'll get
PV= (mass/Mr)*RT
u need to find Mr so now make Mr as a subject
PV= (mass/Mr)*RT do cross multiplication and you'll get
MrPV= mass*RT
Mr= (mass*RT)/(PV)
and now just substitute the values
don't forget to convert cm3 to m3 (just divide by 10^6) , Celsius to Kelvin (to convert celsius to kelvin you just add celsius value to 273 and you'll get kelvin) , also change Kpa to pa (multiply by 1000)
R is constant = 8.31
:)

Answer 4

@Whitemonsterbunny17

Answer 5

its ideal gas law sony kinda explain but I'm still confused

Answer 6

I'm sorry, I have no idea how to do this stuff, I wish I could've been more helpful :c

Answer 7

thanks anyway

Answer 8

@RANE

Answer 9

sony tried to explain but she just confused me

Answer 10

that needs time
but currently im in class
is it okay if i explain it later on?

Answer 11

oh ok ill wait till ur done with class

Answer 12

well, afetr this class i have another class
so im basically finishing after almost 6hrs

Answer 13

oh ok thanks anyway

Answer 14

sorry

Answer 15

@ParthKohli

Answer 16

sony tried to explain but it just confused me

Answer 17

@Karina1 do you know about formulas
\[Mole = mass \div Mr\]
\[PV = nRT\]