The balanced chemical reaction:
2Na + Cl2 = 2NaCl
We are given the amount of sodium chloride to be produced from the reaction. This will be the starting point of our calculations.
29 g NaCl ( 1 mol NaCl / 58.44 g NaCl ) ( 1 mol Cl2 / 2 mol NaCl ) = 0.25 mol Cl2
We use the ideal gas equation to solve for the volume of chlorine gas needed.
V = nRT / P
V = 0.25 (0.08206) (37+273.15) / (682/760)
V = 7.09 L Cl2