Question

I need help with chemistry

Answer 1

PV = nRT

P is pressure in Pa
n is moles (mol)
T is temperature in Kelvins
Volume in m^3
R is the gas constant

R has the value 8.314 J. K. mol−1 or 0.08206 L

Answer 2

to change Celsius to Kelvin, you add 273.15

Answer 3

Well, I did this

(624atm)*(0.02L) / (0.082) * (302.15 K) =22.09

Answer 4

622*

Answer 5

you can also use

1 torr = 133.322 PA
1 ml = 1cm^3 = 1 * 10^-6

Answer 6

You don't have them in the correct units. We need pressure in Pascals not atm. Also the constant is 8.314

20 mL = 0.02L

now use 1 L = 0.001 m^3

and change L to m^3

Answer 7

(6.302 Pa) (0.00002 m^3) / (8.314) (302.15 K) = 50.17 ?

Answer 8

I believe pressure should be in atm
volume in liters
so you can easily cancel units with (\[\frac{ L \cdot atm }{ k \cdot mol }\]

Answer 9

how did you get `624atm`
given pressure is 622 torr

Answer 10

1 atm =760 torr
important conv. to memorize :=))

Answer 11

I know I put 622*, it is same answer I think :/

Answer 12

oh no not at all i'm pretty sure \[\large\rm 622 torr \cancel{= }622 atm\]

Answer 13

\[ \large\rm 622 ~torr ( \frac{1 atm}{760 torr})\]
convert to atm

Answer 14

make sense ?

Answer 15

Yes, I am trying to solve it

Answer 16

(0.818421 atm) (0.02 L) / (0.082) (302. 15 K) , right?

Answer 17

ohh okay nice!

Answer 18

looks good
what about the units ?
first write all the variables with their values and unit
P= 0.8184 atm
V= 0.02 L
\[\large\rm R=0.0821 ( \frac{L \cdot atm}{ mol \cdot K})\]
T= 302 k
now plugin the numbers
\[\large\rm PV=nRT \]
\[\large\rm (0.8184 atm)(0.02 L) = n~ (0.0821 \frac{ L \cdot atm}{ mol \cdot K}) (302 K)\]

\[\large\rm (0.8184 atm)(0.02 L) = n~ (0.0821 \frac{ L \cdot atm}{ mol \cdot \cancel{k}}) (302 \cancel{K})\]

Answer 19

everywhere I read, it said pressure had to be in Pascals mhm

Answer 20

Is it 66.02 ? @_@

Answer 21

hmm then how would we cancel atm from R unit
\[\large\rm (0.8184 atm)(0.02 L) = n~ (0.0821 \frac{ L \cdot \color{Red}{atm}}{ mol \cdot \cancel{k}}) (302 \cancel{K})\]
we can't change R value

Answer 22

idk yet let me solve it first :D

Answer 23

Sure :)

Answer 24

turns out, there are multiple R value, I was just using a different value for R xD
http://prntscr.com/c6829i

Answer 25

doing what nnesha wrote out in the equation, your answer isn't correct .-.

Answer 26

do you mean 66.02 in grams or mol ??

Answer 27

i think you messd up converting mol to g @_@

Answer 28

I'm going to let Nnesha take over. It's been a while since I've done this ;b

And yeah :b

Answer 29

`turns out, there are multiple R value, I was just using a different value for R xD http://prnt.sc/c6829i `
according to the link you don't have to convert P torr to atm or pa
you can keep it in torr and use the 2nd R value in that link

Answer 30

Don't worry, I finally solved it. :D

Answer 31

nice what did you get ?? :D

Answer 32

It is 0.00066 mol and I multiply by 44.0 so it is 0.0290g

Answer 33

haha nice job!

Answer 34

Thank you. I need help with 2 questions. Can you help me?

Answer 35

hmm not sure i gtg will be back later (hopefully)

Answer 36

It's fine, thanks again :D

Answer 37

yw