1. The Rydberg equation can be used to predict the spectral emissions of hydrogen atoms.
RH = 1.097 x 10^7 m^-1; c = 3.00 x 10^8 m/s; h = 6.626 x 10-34 Js
a) The Balmer series is the series of emissions arising from the fall of an electron from a higher orbital to the n=2 orbital. Calculate the wavelength of the lowest energy transition in the Balmer series.
b) The Lyman series is a set of emissions arising from the fall of an electron from a higher orbital to the n=1 orbital. Do you expect emissions in this series to be higher in energy or lower than the Balmer series? Explain.
2. When hydrogen sulfide gas (H2S) is bubbled into a solution of sodium hydroxide (NaOH), the reaction forms sodium sulfide (Na2S) and water. How many grams of sodium sulfide are formed if 3.50 g of hydrogen sulfide is bubbled into a solution containing 4.20 g of sodium hydroxide, assuming that the sodium sulfide is made in 73% yield?
3. Imagine a car cylinder of roughly .250 L volume (which is not an unreasonable volume). For the most efficient combustion event, O2 and fuel must be added in stoichiometric amounts. The combustion of gasoline can be approximated with the reaction:
____C8H18 + ____ O2 à ____ CO2 + ____ H2O
a) The cylinder is pressurized from ambient pressure (1 atm) to 10 psig, or 1.33 atm. This pressure is predominantly from air. The engine is running at 95 oC. How many moles of gas are present in the cylinder? (R = 0.0821 (L atm)/(mol K))
b) Air is 21% oxygen. What mass of fuel must be injected with the amount of air in a) for the reaction to proceed in exactly stoichiometric amounts?
c) What will be the pressure in the cylinder after combustion once it has been pushed back out all the way (so volume is again .250L)?
4. A column of mercury 4.8 mm high exerts the same pressure as the atmosphere on Mars. The density of mercury is 13.54 g/cm3. The radius of the Mars is 3390 km. The surface area of a sphere is 4πr2. What is the mass of the atmosphere of Mars? (You may assume that gravity is constant throughout the region of the atmosphere where the bulk of the mass of the atmosphere is)