Question

During the process of titrayion of antiacid made of calcium carbonate the first step is to add excess hydrochloric acid to antacid to observe bubbling which is forming of carbon dioxide CaCO3(s) + 2HCl(aq) -------> CaCl2(aq) +CO2(g) + H2O (I) Because this carbon dioxide reacts with water to form carbonic acid and increase the overall concentration of acids, removing carbon dioixde is an essential process for an accurate experiement A) you are given a 1.50g antiacid tablet made of calcium carbonate and some filter materials. If you found that 0.015 moles of HCl is used exactly to titrate calcium carbonate instead of excess hydrochloric acid how many grams of CaCO3 you had in your tablet? B) What percentage of the sample give to you is CaCO3?

Answer 1

A.CaCO3(s) + 2HCl(aq) -------> CaCl2(aq) +CO2(g) + H2O (I)

2 moles of HCl react with 1 mole of CaCo3

0.015 moles of HCl react with = 1*0.015/2 = 0.0075 moles of CaCo3

mass of CaCo3 = no of moles * gram molar mass

                            = 0.0075*100

                             = 0.75 g of CaCO3

B.

The percentage of CaCO3 in the sample = mass of CaCO3*100/mass of sample

                                                                    = 0.75*100/1.5   = 50% >>>>>answer