CH304K S2021

Exam 1

Thursday 2/11

ChemBook Chapters:
Chapter 0: Stuff You Already Know
Chapter 1: Fundamentals of Chemistry
Chapter 2: Atmosphere, Air, and Gases

Learning Outcomes

Students will know...

  1. how to count stuff
  2. that fire is hot
  3. how to mathematically convert from one type of unit to another utilizing a set of conversion factors
  4. the names, formulas, and physical state of the first 10 alkanes
  5. Know which elements exist as diatomic molecules
  6. the MAIN Metric Prefixes for Chemistry Class as listed in section 10.2 of chembook - it's the last table there
  7. how to fully balance a chemical reaction and identify the coefficients
  8. how to do composition stoichiometry calculations - figuring out the percent of a specific element in a given compound
  9. how to do reaction stoichiometry calculations converting moles to moles and also moles to grams and grams to grams or anything else
  10. how to predict product amounts when given arbitrary amounts of reactants - limiting reactant problems (like #20 on HW01)
  11. the same outcomes as the two previous ones but with gas moles using the ideal gas law to get pressure or volume of the gas reactants.
  12. the 3 primary components and their percentages of dry air
  13. how those percentages change when humid air is used
  14. the 6 primary pollutants in our air - know names and formulas and/or abbreviations for them
  15. the primary sources/causes of those pollutants
  16. what methods are in place to help curb the amounts of these pollutants in air
  17. how to calculate various gas law values - P, V, T, and n according to the ideal gas law and associated laws
  18. how to convert pressure of a gas into number (mole) density
  19. what partial pressure is and how to calculate it.
  20. how to get mole fraction from partial pressure and total pressure and vice versa
  21. how to use the pressure and identity of a gas to calculate its mass density
  22. how to convert mass density and pressure into the molecular weight of a gas
  23. anything else we learned and did in class, on HW, that I forgot here

More Help on Exam 1

Jimmy's Help Videos on Exam 1 topics.

Formulas YOU should know

The Ideal Gas Law (IGL):


Gas Laws "contained" in the IGL:

Boyle's Law:    \(P_1V_1 = P_2V_2\)    (constant n, T)

Charles' Law:    \(\displaystyle{V_1\over T_1} = {V_2\over T_2}\)    (constant n, P)

Avogadro's Law:    \(\displaystyle{V_1\over n_1} = {V_2\over n_2}\)    (constant P, T)

Gay-Lussac's Law:    \(\displaystyle{P_1\over T_1} = {P_2\over T_2}\)    (constant n, V)

Inflate a Tire Law:    \(\displaystyle{P_1\over n_1} = {P_2\over n_2}\)    (constant V, T)

Nobody Does This Law:    \(n_1T_1 = n_2T_2\)    (constant P, V)

(note that you will be tested on the actual relationships of the physical properties and not the scientist's names)

and because density (ρ) is m/V and molar mass (M) is m/n, then you also know the molar mass of an ideal gas via:

\[{M={\rho RT\over P}}\]

Dalton's Law of Partial Pressures
\[P_{\rm total}=P_{\rm A} + P_{\rm B} + P_{\rm C} + \cdots\]

mole fraction of gas A:   \(x_{\rm A}=P_{\rm A}/P_{\rm total}\)

Practice Problem Sets

Here are two practice problem sets for you to work on and get some experience working through these types of problems.

Composition Stoichiometry Extra Practice.pdf

Gas Law Stoichiometry Extra Practice.pdf

Sorry, but we do not have any answer keys to these problem. Talk with other students about the problems and try to reach a correct conclusion/answer.

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