Calculate Pressure Increase of an Aerosol in Sunlight

[ibysaiyan]

Homework Statement

An Aerosol has a of pressure 250kpa at 17 C.The aerosol is left in the sun and its temp.rises to 27 C.Calculate new pressure in the can if its a 35% increase in the amount of vapour present.

Homework Equations

P/T= constant

The Attempt at a Solution

well tbh i am just confused.. do i get T= into kelvin, ok i tried that too...
my first attemp was:
1)(273.15+27)-(17+273.15)=10kelvin
so what i did:10x250x10^3/100= 25kPa
so pressure at 27 is: 250+25=275Kpa
2)
2nd attempt:
PV=nRT
P/T=nr/v
=>P/T= constant
250x10^3/10kelvin=25kpa... which if i add to 250 gives me same answer.. lol i have confused my self badly -(. first i forgot to convert C into Kelvin .
Thanks for the replies in adv.

 

[RoyalCat]

Try and work in an ordered way. Always try and structure your work in advance. Write out what you know, and what you're looking for.

And I think you shouldn't work with P/T=constant
That's just a misleading way of saying that the volume is constant, and I think it can only lead to confusion.

Initial state:

P_1 V_1 = nRT_1

P_1= 250kPa

V_1=V_2 (As long as the can doesn't deform, its total volume remains the same)

T_1=(17+273.15) ^o K

Final state:

P_2 V_2 = nRT_2

We are looking for P_2

V_2=V_1

T_2=(27+273.15) ^o K

Now all that you need to do is isolate P_2 and express it in terms of known quantities.

 

[ibysaiyan]

ermm sorry i don't get it , do you mean that i should isolate p2 =nRT2/v2

 

[RoyalCat]

ermm sorry i don't get it , do you mean that i should isolate p2 =nRT2/v2

Yes...
Now find a way to express V_2 in terms of known quantities.