Hydrogen produced from a hydrolysis reaction was collected over water. The data is compiled in the table. Total volume of H2(g) collected 95.79 mL Temperature 24.0 °C Barometric pressure 745 mmHg Vapor pressure of water at 24.0 °C 22.5 mmHg Calculate the moles of hydrogen gas produced by the reaction. moles: mol H2

What is the experimental molar mass (that is, calculated from the data given and not taken from the periodic table) of magnesium if 0.0157 grams of magnesium generates 15.92 mL of hydrogen at 23.6 °C with a hydrogen partial pressure of 747.1 torr? Note that the partial pressure of water vapor has already been subtracted from the total pressure. 20.4 g/mol 24.4 g/mol 25.1 g/mol 22.1 g/mol 25.2 g/mol

Air entering the lungs ends up in tiny sacs called alveoli. It is from the alveoli that oxygen diffuses into the blood. The average radius of the alveoli is 0.0041 cm, and the air inside contains 14 percent oxygen. Assuming that the pressure in the alveoli is 1.0 atm and the temperature is 37 °C, calculate the number of oxygen molecules in one alveolus. For calculation purposes, assume that the average alveolus is a perfect sphere. Be sure your answer has the correct number of significant digits. Note: Reference the Fundamental Constants table for additional information. 8.486 x 10 10° | molecules x10

Assume that 3.51x10^6  kJ of energy is needed to heat a home. If this energy is derived from the combustion of methane(CH4) , what volume of methane, measured at STP, must be burned? (Delta H of combustion for CH4  = –891 kJ/mol) Volume =  L