Science Homework Help

1. According to the ideal gas law, a 0.9150 mol sample of nitrogen gas in a 1.753 L container at 265.8 K should exert a pressure of 11.38 atm. By what percent does the pressure calculated using the van der Waals’ equation differ from the ideal pressure? For N₂ gas, a = 1.390 L²atm/mol² and b = 3.910E-2 L/mol.

2. Aluminum reacts with aqueous sodium hydroxide to produce hydrogen gas according to the following equation:

2Al(s) + 2NaOH(aq) + 6H₂O(l)—>2NaAl(OH)₄(aq) + 3H₂(g)

The product gas, H₂, is collected over water at a temperature of 25 °C and a pressure of 759 mm Hg. If the wet H₂ gas formed occupies a volume of 7.01 L, the number of moles of Al reacted was _____ mol. The vapor pressure of water is 23.8 mm Hg at 25 °C.

3. Calcium carbide reacts with water to produce acetylene gas according to the following equation:

CaC₂(s) + 2H₂O(l)—>C₂H₂(g) + Ca(OH)₂(aq)

The product gas, C₂H₂, is collected over water at a temperature of 20 °C and a pressure of 743 mm Hg. If the wet C₂H₂ gas formed occupies a volume of 9.86 L, the number of grams of C₂H₂ formed is ____ g. The vapor pressure of water is 17.5 mm Hg at 20 °C.