Announcements - University of Illinois at...
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10/19/2012 1 Announcements • Lon-Capa Homework #7 due next Wednesday 10/19/2012 1 From your textbook (A&J) • Chapter 4 The Property of Gases (p.133) • What Do We Need to Know Already – “We need to be familiar with SI units (Appendix 1B) and the concepts of force and energy (Section A). This chapter also extends the techniques of reaction stoichiometry (Sections L and M) • If you need to catch up on the basics, – A worksheet on gases will be available to download (in Lon-Capa) for practice 10/19/2012 2
Transcript of Announcements - University of Illinois at...
10/19/2012
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Announcements
• Lon-Capa Homework #7 due next Wednesday
10/19/2012 1
From your textbook (A&J)
• Chapter 4 The Property of Gases (p.133)
• What Do We Need to Know Already
– “We need to be familiar with SI units (Appendix 1B) and the concepts of force and energy (Section A). This chapter also extends the techniques of reaction stoichiometry (Sections L and M)
• If you need to catch up on the basics,
– A worksheet on gases will be available to download (in Lon-Capa) for practice
10/19/2012 2
10/19/2012
2
The reaction used in the deployment of automobile airbags
is the high-temperature decomposition of sodium azide, NaN3,
to produce N2 gas. How many liters of N2 at 1.15 atm and
30.0 °C are produced by decomposition of 45.0 g NaN3?
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Example - Stoichiometric Relationships with Gases
2Na(s) + 3N2(g) 2NaN3(s)
Example
A 12.5 L Scuba diving tank is filled with a heliox mixture containing 24.2 g He and 4.32 g O2 at 298 K.
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Given: Mass He = 24.2 g Mass O 2 = 4.32 g V = 12.5 L
Need to find: He = ? O2 =? Phe = ? PO2= ? Ptotal =?
Calculate the mole fraction and partial pressure of each component in the mixture. What is the total pressure of the tank?
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Ptotal = 𝑛𝑡𝑜𝑡𝑎𝑙𝑅𝑇
𝑉
the mole fraction () = 𝑛𝑖
𝑛𝑡𝑜𝑡𝑎𝑙 =
𝑃𝑖
𝑃𝑡𝑜𝑡𝑎𝑙
Ptotal = P1 + P2 + P3 + …..= 𝑛1𝑅𝑇
𝑉+ 𝑛2
𝑅𝑇
𝑉+ 𝑛1
𝑅𝑇
𝑉+ …
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