//calculating lime and soda //Example 1.8 clc clear //For raw water Ca+2, q1=240//quantity wt1=40//molecular weight M1=100/wt1//multiplication factor Eq1=M1*q1//CaCO3 equivalents in mg/L //For Mg+2, q2=96//quantity wt2=24//molecular weight M2=100/wt2//multiplication factor Eq2=M2*q2//CaCO3 equivalents in mg/L //For CO2, q3=44//quantity wt3=44//molecular weight M3=100/wt3//multiplication factor Eq3=M3*q3//CaCO3 equivalents in mg/L //For HCO3-, q4=732//quantity wt4=122//molecular weight M4=100/wt4//multiplication factor Eq4=M4*q4//CaCO3 equivalents in mg/L //For FeSO4.7H2O, q5=278//quantity wt5=278//molecular weight M5=100/wt5//multiplication factor Eq5=M5*q5//CaCO3 equivalents in mg/L V=250000//Volume of water in litres L=(74*(Eq2+Eq3+Eq4+Eq5)/100)*(V/1000000)//lime requirement in kg S=(106*(Eq1+Eq2+Eq5-Eq4)/100)*(V/1000000)//soda requirement in kg printf('Thus amount of lime required to soften 250000 litres of water = %3.1f kg\n',L) printf('and amount of soda required to soften 250000 litres of water = %3.1f kg\n',S)