Question

How many grams of chlorine gas (Cl2) are in a 17.8 liter sample at 1.1 atmospheres and 29 degrees C?

can someone help me understand this...im not sure how to do it, i think it might be the percent catching me off guard...can someone explain to me how to get the answer?

Answer 1

@Rushwr can you help me with this?

Answer 2

use PV=nRT

Answer 3

let me tell u the easy way to solve these
first write down the data u are given with
We know the volume (V), Pressure (P) and temperature (T)
R is the universal gas constant
now u can see we know all the data needed except no. of moles (n) in PV=nRT equation right?
We know moles = mass divided by molar mass
Molar mass of Cl2 is approximately 71gmol^-1

Answer 4

first find the moles or else u can directly substitute m/M instead of n in the equation
m= mass
M= molar mass

Answer 5

Can u try and get the answer here !

Answer 6

ok give me a sec and ill try :)

Answer 7

how do i get the mass?

Answer 8

moles = mass divded by molar mass
moles is the n in the equation instead of PV=nRT we can write the equation like PV=(m/M)RT right?

Answer 9

P = pressure = 1.1 atm
V = volume = 17.8 L
n = number of moles Cl2 (unknown)
R = gas constant = 0.08206 L*atm/mol*K
T = temperature = 29C + 273.15 = 302.15 K

Answer 10

ok that kinda makes sense...

Answer 11

these are the data.
Make sure that u convert ur temperature to kelvin

Answer 12

where did the 273.15 come from?

Answer 13

\[PV= nRT\]
\[n= \frac{ m }{ M }\]
\[PV= \frac{ m }{ M }RT\]

Answer 14

When u convert a temperature from Celsius to kelvin u need to add 273.15 to the Celsius value to convert t to kelvin

Answer 15

I hope that makes sense. oh u can also add 273 approximately

Answer 16

so i would use that number every time i converted celcius to kelvin or just for this?

Answer 17

yes exactly

Answer 18

@AlexisIB Make sure that u are thorough with the conversions

Answer 19

ok what do i do with everything now? do i multiply?

Answer 20

do i keep it like it is?

Answer 21

now substitute the values

Answer 22

ok...not to sound stupid but how do i do that? :(

Answer 23

PV= nRT
right?
First we are gonna find moles (n)
We know pressure (P) = 1.1 atm
Volume (V) = 17.8L
Universal gas constant (R) = 0.08206 L*atm/mol*K
Temperature (T) = 29+273 = 302K

Answer 24

now get the value for n !

Answer 25

ok but i still dont know how...but ill call my teacher, thanks for helping me though

Answer 26

no problem . And sorry for late replies my OS is lagging

Answer 27

@Rushwr i think i figured it out without calling my teacher...can you check to see if im right so far?

Answer 28

@mayankdevnani can you check?

Answer 29

P=1.1
V=17.8
R=.0821
T=29' C + 273.15 = 302.15 K
(always use 273.15 when converting from degrees to kelvin)

1.1 x 17.8 / 0.0821 x 302 =0.7895

Mass= .7895 mol x 70.906 g/mol

Answer 30

yup !
good job :) @AlexisIB

Answer 31

I'm sorry I was a little late for this. Anyways yeah great job @AlexisIB

Answer 32

thank you!!! im so happy that i actually did it!!

Answer 33

:)

Answer 34

both of you are awesome :)

Answer 35

lol thanks

Answer 36

you are awesome @AlexisIB

Answer 37

YOUR HARDWORK PAYS OFF !

Answer 38

Thanks!!

Answer 39

your welcome :)