A piece of sodium metal reacts completely with water as follows:

2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g)

The hydrogen gas generated is collected over water at 29.0°C. The volume of the gas is 181 mL measured at 0.981 atm. Calculate the number of grams of sodium used in the reaction. (The vapor pressure of water at 29.0°C = 0.0395 atm.)

g