How many grams of sodium metal are needed to react completely with 25.8 liters of chlorine gas at 293 Kelvin and 1.30 atmospheres?

Ideal gas law after stoichiometry

Respuesta :

First, we need to get the moles of Cl2 ( chlorine)

we can use the ideal gas formula to get n ( moles of gas) :

PV = nRT

when p is the pressure = 1.3 atm 

and V is the volume = 25.8 L 

R is the constant of the ideal gas = 8.314

T temperature in Kelvin = 293 

∴ n = PV / RT

      = 1.3 * 25.8 / 8.314* 293

      = 0.0138 moles 

according to the reaction equation:

2Na(s) +Cl2 → 2 NaCl 

we can see from the balanced equation that the molar ration between Na & Cl2 = 2: 1 

∴ moles of Na = moles of Cl2 / 2
                        = 0.0138 / 2
                        = 0.0069 moles 

now, we have the moles of Na and by using the molar mass of Na = 22.99 g/mol 

∴ Mass of Na = moles of Na * molar mass  

                       = 0.0069 moles * 22.99

                      = 0.1586 g