Question

In the lab: extraction, purification and analysis of turmeric natural products, Calculate the amount of 3M HCI that would be needed to neutralize the 35 mL of 1M NaOH used in the extractions when you add 20mL 1M NaOH and 10mL saturated sodium chloride to a seperatory funnel which contains 5mL turmeric (extracted from MTBE) and 5 mL of MTBE, shake it, seperating the layers.. You then drain the lower aqueous layer into a flask and leave the top (MTBE) layer in the seperatory funnel and extract it a second time with 15 mL 1M NaOH then combine the NaOH layer with the previous layer in a flask and save for later..

Answer 1

HCl      +    NaOH ------> NaCl + H2O

1 mole      1 mole

HCl                                                                                         NaOH

molarity M1 = 3M                                                          molarity M2 = 1M

volume   V1 =                                                                volume V2 = 35ml

no of moles n1 = 1                                                         no of moles n2 = 1

M1V1/n1        =     M2V2/n2

V1              = M2V2n1/n2M1

                  = 1*35*1/1*3     = 11.67ml

no of moles of HCl = molarity * volume in L

                          = 3*0.1167 = 0.3501 moles

mass of HCl    = no of moles of HCl* molar mass of HCl

                    = 0.3501*36.5 =12.77gm

amount of HCl is 12.77gm >>>>> answer