The number of grams of Cl2 formed when 0.115 moles of HCl react with O2 is calculated as follows
write the chemical equation
4HCl + O2 -----> 2H2O + 2Cl2
if 0.115 moles of HCl reacted and from the equation above the reacting ratio between HCl and Cl2 is 4:2 therefore the moles of Cl2= 0.115 x2/4=0.0575moles
mass of Cl2= moles x molar mass of Cl2(35.5 x2=71g/mol)
=0.0575 moles x71g/mol = 4.0825 grams
