11. A 2.0 L balloon is filled with a mixture of helium and nitrogen. Assuming that this occurs at 250C and atmospheric pressure (1.00 atm), answer the following questions. a)The pressure within the balloon is 1.00 atm (the same as the atmospheric pressure). Explain how you know this is true.
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b)How many total moles of gas were used to fill the balloon?
c)If the partial pressure of He in the balloon is 0.8 atm, what is the partial pressure of N2in the balloon? What is the mole fraction of N2in the balloon?
d)What is the density of He in this balloon?
b)
Which of these two gasses would you expect to effuse out of the balloon faster and why?
CHEM 111 Exam 2 Fall 2016 /4 Constants and equations: Speed of light: c = 2.997x108ms-1Plank’s constant: h=6.626x10-34J∙s 1 J = 1 kg∙m2∙s-2charge of an e-: e = 1.602x10-19C mass of e-: me=9.11x10-31kg mass of p+: mp=1.67x10-27kg 𝐸𝐸=ℎ ∙ 𝜈𝜈Avogadro’s constant: NA= 6.022x1023mol-1DeBroglie Relation: 𝜆𝜆=ℎ𝑚𝑚∙v=ℎ𝑝𝑝𝐸𝐸=−2.18 × 10−18𝐽𝐽 ∙ �𝑍𝑍2𝑛𝑛2�∆𝐸𝐸=−2.18 × 10−18𝐽𝐽 ∙ �𝑍𝑍2𝑛𝑛𝑓𝑓2−𝑍𝑍2𝑛𝑛𝑖𝑖2�c = λ∙ νPV=nRT 𝑢𝑢𝑟𝑟𝑚𝑚𝑟𝑟=�3𝑅𝑅𝑅𝑅𝑀𝑀𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝑟𝑟𝐸𝐸𝐸𝐸𝑛𝑛𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝐺𝐺𝑅𝑅𝑟𝑟1𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝐸𝑟𝑟𝐸𝐸𝐸𝐸𝑛𝑛𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝐺𝐺𝑅𝑅𝑟𝑟2= �𝑀𝑀2�𝑀𝑀1�𝑃𝑃+𝐶𝐶 �𝑛𝑛𝑉𝑉�2�(𝑉𝑉 − 𝑖𝑖𝑛𝑛) =𝑖𝑖𝑛𝑛𝑇𝑇𝑛𝑛= 0.08206𝐿𝐿∙𝑅𝑅𝑅𝑅𝑚𝑚𝑚𝑚𝐸𝐸𝑚𝑚∙𝐾𝐾= 8.31451𝐽𝐽𝑚𝑚𝐸𝐸𝑚𝑚∙𝐾𝐾𝐾𝐾𝐸𝐸=12𝑚𝑚v2=32𝑛𝑛𝑇𝑇ΔE= q+ww=-PΔVq=mcΔT𝐸𝐸𝑅𝑅𝑚𝑚∝𝑄𝑄1𝑄𝑄2𝑑𝑑
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- Spring '08
- Kenney
- Chemistry
