##### ​(a) An ideal gas occupies a volume of 1.8 cm3 at 20°C and atmospheric pressure.

label Physics
account_circle Unassigned
schedule 1 Day
account_balance_wallet \$5

(a) An ideal gas occupies a volume of 1.8 cm3 at 20°C and atmospheric pressure. Determine the number of molecules of gas in the container.

molecules

(b) If the pressure of the 1.8-cm3 volume is reduced to 2.4 ✕ 10−11 Pa (an extremely good vacuum) while the temperature remains constant, how many moles of gas remain in the container?
mol

Jun 26th, 2015

Thank you for the opportunity to help you with your question!

we know that PV = nRT  ;  therefore    n = PV/RT
P = 1.00 atm ; V = 1.8 cm³ =  0.0018 Liters ; R = 0.0821 L atm/mole K
T = 20°C =  293.15K

n = (1.00) x (0.0018) / [ (0.0821) x (293.15K) ]
n = 7.48x10^(-5) moles

7.48x10^(-5) x (6.022x10^23  / 1 ) = 4.50x10^(19) molecules.

(B) P = 2.4 x10 ^(-11) Pa = 2.4 x10^(-11)  x 9.9 × 10-6  atm = 23.76 x 10^(-17) atm

; V = 1.8 cm³ =  0.0018 Liters ; R = 0.0821 L atm/mole K

n = (23.76 x 10^(-17)) x (0.0018) / [ (0.0821) x (293.15K) ]
n =0.00177 x10^(-17)   or   1.77 x 10^(-20)  moles

Please find the solution enclosed here with .. In case of any doubt please feel free to ask… Do not forget to best my answer… If you are having some other problem please feel free to contact me for quick & quality services..
Jun 26th, 2015

Jun 26th, 2015
screen_shot_2015_06_25_at_10.52.08_pm.png

...
Jun 26th, 2015
...
Jun 26th, 2015
Oct 22nd, 2017
check_circle
Mark as Final Answer
check_circle
Unmark as Final Answer
check_circle

Secure Information

Content will be erased after question is completed.

check_circle