A student add a total of 15.00 m L of .5432 HCl to their unknown alkaline earth carbonate .it completely dissolved and stopped fizzing . Addition of 3 drops of bromophenol blue confirmed the solution was acidic. The solution required 12.3 m L of 12.34 m L of 0.1255 M NaOH to back titrate theexcess HCl.
1) What was the total number of moles of HCl add to the unknown ?
2) How many moles of excess HCl were added?
3) How many moles of MCO3 werepresent in the original unknown ?
4) If the mass of the originalunknown was .04871 g , and the unknown was 100% MCO3 . what is theformula mass of the carbonate ?
5) Identify unknown ?