Question

Calculate the amount of water you need to add (in mL) to 30mL of 1.5M HCl to dilute it to a concentration of 1.25M.

Answer 1

1.5M=1.5mol/dm3 And 0.30ml=30cm3=0.03dm3 So First We Find The No# Of Moles Of HCl Present n=M(conc)*vol(dm3)=1.5*0.03=0.045mol Using Mole Ratios NaOH+ HCl~>H2O+Nacl 1/1=0.045mol/x x=0.045mol Of H2O Therefore volume of a water n(0.045*1.25/1.5)/conc(1.25) now finish it by carying out the calculations