homework help

[Sabby]

alot of the people here are older than me so this question should be easy, and since there is no board for this, i will ask here. this is science and it involves boyle's law.i already know how to set up the formula witch in my question would be "P2=(22.5 kPa)(155 cm cubed)divided by 90 cm cubed" and P stands for pressure. it wants me to solve for P2. ??? ???

[えっちーせんぱい]

What the hell is that?

[Sabby]

it a stupid science question, i hate formulas. :(

[Silverhawk79]

Eh...too bad I got a C+ in Chemistry. >_>

[Sabby]

here is a better layout
       (22.5 kPa)(155 cm cubed)
P2=-----------------------------------
                  90 cm cubed

[Doodle]

Ummm... I have no clue...  ???

[phatyo]

The anwer is p=42 your done

[Doodle]

The anwer is p=42 your done

Did you ACTUALLY do that!?

[Sabby]

how the heck did you do that? ???

[Sabby]

i need more help with HOW to do it, because i have more questions like it.

[phatyo]

i need more help with HOW to do it, because i have more questions like it.

On the old Nsider there was a home work help team :/ some one needs to come up with the same thing here!

[Sabby]

actually that would have to be wrong. if volume 2 is less than volume 1, wouldn't pressure 2 be less than pressure 1?(pressure 1 is 22.5 kPa)

[Silverhawk79]

Don't you just have to multiply the top two numbers, and then divide by the bottom? >_>

[Sabby]

Don't you just have to multiply the top two numbers, and then divide by the bottom? >_>

that is the first thing i though, but then i thought that would be multiplying the pressure into the volume, and it seems weird to do that.

[Omega Pirate]

Boyle's Law:
P1 * V1 = P2 * V2


P1 = 22.5kPa
V1 = 155 cm^3

P2 = ?
V2 = 90cm^3


So.....we plug in the values:

22.5 * 155 = P * 90

=

3,487.5 = P * 90


Solve for P by dividing 3,487.5 by 90, and: 38.75kPa.


Gas laws are actually very simple. Just plug in the values you have, and then just do the basic algebra to finish it off. I never got it at first either, but trust me, once you do get it, you will feel really dumb for not getting it sooner. I sure as heck did.