How many grams of chlorine gas (cl2) are in a 17.8 liter sample at 1.1 atmospheres and 29°c? show all work used to solve this problem.

By using the ideal-gas equation: PV = nRT 

where: 
P = pressure = 1.1 atm 
V = volume = 17.8 L 
n = number of moles Cl2 (unknown) 
R = gas constant = 0.08206 L*atm/mol*K 
T = temperature = 29C + 273.15 = 302.15 K 
To calculate number of moles of Cl2
(1.1 atm)*(17.8 L) = n*(0.08206 L*atm/mol*K)*(302.15 K) 
n = 0.79 moles Cl2 

Convert moles Cl2 to grams Cl2. 
Note: 1 mole Cl2 = 70.9064 grams Cl2 

0.79 moles Cl2 x (70.9064 grams Cl2/1 mole Cl2) = 56.0 grams Cl2