Answer to Question #59450 in General Chemistry for Zoey Chua

Question

1. The concentration of ammonia in commercially available cloudy solution used for
cleaning was conducted in a laboratory.
25.00mL of the cloudy ammonia solution was pipetted into a 250.00mL conical flask.
50.00mL of 0.100N HCl was immediately added to the conical flask which reacted
with the ammonia in solution.
NH3 (aq) + HCl (aq) NH4Cl (aq)
The excess HCl was then titrated with 0.050M Na2CO3.
21.50mL of Na2CO3 was required for the titration.
2HCl (aq) + Na2CO3 (aq) 2NaCl (aq) + CO2 (g) + H2O (aq)
Calculate the concentration of the ammonia in the cloudy solution, in Molarity.

2. There are 9 points discussed in Analytical Method Validation. Consider a titration between an acid and a base with the use of an indicator, state which 3 ( amongst the 9) are most important and your reasons.