empirical and molecular formulas

1. Ethylene glycol is used as automobile antifreeze. 6.38g og this compound contains 2.47g of carbon and 0.620g of hydrogen. The rest is oxygen. The molar mass is 62.0g/mole. What are the empirical and molecular formulas of ethylene glycol? (observe significant digits)

STP and volume

1. The respiratory rate of a person is 20 breathes per minute. If every average breath is about 310cm^3 of air at 22C and 740mmHG, what volume of air in cubic meters and corrected to standard temperature and pressure conditions does a person breathe in one day?

Wavelength

The silver iodine bond energy is approx 255kJ/mol. (AgI is one of the active components in photograpgy sunglasses.) What is the longest wavelength of light capable of breaking the bond in silver iodine?

theoretical yield

What is the theoretical yield of vanadium that can be produced by the reaction of 40.0 g of V2O5 with 40.0 g of calcium based on the following chemical reaction. V2O5(s) + 5Ca(l) --> 2V(l) + 5CaO(s)

Reaction

Chlorine gas can be prepared in the laboratory by the reaction of manganese dioxide with hydrochloric acid: MnO2(s) + 4HCl(aq) --> MnCl2(aq) + 2H2O(l) + Cl2(g) How much MnO2 should be added to excess HCl to obtain 275mL of chlorine gas at 5.0C and 650 mmHg?