4. Titarant in Mohr 's method is 1) AgNO_(3) solution; 2) KSCN solution: 3) Hg_(2)(NO_(3))_(2) solution; 4) NaCl solution 5) K_(4)[Fe(CN)_(6) solution Explain your answer. Provide theoretical/practical information as much as you can (examples,, chemicals reactions, etc.)

The correct answer is 1) $AgNO_{3}$ solution.<br /><br />In Mohr's method, the titrant used is $AgNO_{3}$ solution. This method is commonly employed for the determination of chloride ions in a solution. The reaction between the chloride ions and the $AgNO_{3}$ solution forms a precipitate of silver chloride (AgCl), which can be measured to determine the concentration of chloride ions in the original solution.<br /><br />The reaction can be represented as follows:<br /><br />$AgNO_{3} + Cl^- \rightarrow AgCl \downarrow$<br /><br />The formation of the AgCl precipitate indicates the endpoint of the titration, and the amount of chloride ions present can be calculated based on the amount of $AgNO_{3}$ solution used.