Finding mass of SO2 gas from pressure, volume and temperature

[kro041193]

Hi! ... How can I anwer this question? please is for tomorrow!

calculate the mass of SO2 contained in a 20-L cylinder exposed to the sun at 40°C if the pressure exerted by the gas is 200 kPa.

Homework Equations

the things I have are:
S= 32 O=16(2) SO2= 62
V= 20-L
T= 40°C = 313 K
P= 200 kPa
R= 8.31

then i made this equation:

n=PV/RT snd i got n= 1.53 mols

then I think I have to make this equation:

M=mRT/PV but i don't know the value of "m" :S

could someone help me?

 

[Borek]

You know number of moles - now just calculate mass.

 

[kro041193]

but with what equation? because the equation that i think i could use .. i can't use it because I am missing a value ... if the equation is M=mRT/PV I am missing the "m" value so i can't do this equation

 

[Borek]

You are overthinking. You have already used ideal gas properties, now go back to the very first chemistry lessons.

What is molar mass of SO₂?

 

[kro041193]

the molar mass of SO2 is 62

 

[Borek]

So what is mass of 1.53 moles of SO₂?

 

[kro041193]

97.92

 

[Borek]

Wasn't that hard.

--
methods

 

[kro041193]

i know! i was so stuck in something really easy! thnx!