Titration and Calculations

Titration

​Titration is a laboratory technique used to determine the concentration of a substance in a solution.

It involves adding a known volume of a solution with a known concentration (the titrant) to a solution of the substance being analyzed (the analyte) until a reaction occurs, and the concentration of the analyte can be calculated based on the amount of titrant needed to complete the reaction.

Titration involves several steps, including:

• Preparation

• Indicator Selection

• Titration

• Calculation

​Preparation of the solutions: The unknown solution is placed in a flask or beaker, and a known volume of the titrant is measured out.

The titrant is usually added to a burette, which is a long, graduated glass tube used for precise measurement of liquid volumes.

​Indicator selection: An indicator is added to the unknown solution, which will change color or signal some other change when the reaction between the unknown and titrant is complete.

​Titration: The titrant is gradually added to the unknown solution while stirring until the indicator signals that the reaction is complete.

The point at which this occurs is called the equivalence point and is the point at which the number of moles of titrant added is stoichiometrically equivalent to the number of moles of the substance being titrated.

​Calculation of results: The volume of titrant required to reach the equivalence point is measured and used to calculate the concentration of the unknown solution.

​In titration, a burette is typically used to add the titrant slowly and precisely to the analyte solution, while the analyte solution is continuously stirred or swirled.

The reaction between the two solutions is typically monitored using an indicator, which changes color or other properties when the reaction is complete.

Multiple Choice

What is this piece of apparatus called

• Pipette

• Burette

• Janette

• Cuvette

Multiple Choice

What is the reading on this burette?

• 24.0cm³

• 25.8cm³

• 24.2cm³

• 23.9cm³

Multiple Choice

Calculate the average volume of acid needed for this neutralisation

• 15.2cm³

• 15.0cm³

• 35.5cm³

• 30.1cm³

Multiple Choice

what is the reading on this burette?

• 4.40mL

• 3.50mL

• 3.60mL

• 4.50mL

Multiple Choice

Acid + Base ₋--> 

• salt + hydrogen

• salt + water

• salt + carbon dioxide + water

• salt

Multiple Choice

HCl + NaOH → 

• NaH + ClOH

• NaCl + H₂

• NaCl + H₂O

• NaCl + Cl₂

Multiple Choice

What indicator is commonly used in titrations?

• Phenolphthalein

• Bromothymol Blue 

• Litmus

• Universal 

Multiple Choice

What is the white tile or white paper for in titration?

• To help clearly see the color change

• To protect the conical flask

• To add extra height

• To assist the reaction

Multiple Choice

If phenolphthalein turns bright pink, it indicates

• an acid 

• a base

• a neutral

Multiple Choice

Which is the stronger acid?

• pH 1

• pH 4

• pH 8

• pH 13

If, for example, your results were:

• 25.0cm3 of sodium hydroxide required 20.0cm3 of 0.100 mol dm-3 hydrochloric acid for neutralisation. 

• What is the concentration of the sodium hydroxide?

Multiple Choice

30mL of NaOH is neutralized by 12.3mL of 0.2M HCl. What is the concentration of the NaOH.

• 82 mol/l

• 0.82 mol/l

• 0.49 mol/l

• 0.082 mol/l

Multiple Choice

The reaction of perchloric acid (HClO4) with lithium hydroxide (KOH) is described by the equation

HClO4 + KOH → KClO4 + H2O

Suppose 100 mL of perchloric acid is neutralized by exactly 50.0 mL of 1.0 M of Potassium hydroxide. What is the concentration of the perchloric acid?

• 0.5M

• 50M

• 2.0M

• 1.0M

Multiple Choice

If it takes 50 mL of 0.5 M Ca(OH)₂ to neutralize 125 mL of hydrochloric acid (HCl), what is the concentration of the acid?

• 0.2 M

• 5 M

• 0.5 M

• 0.4 M

Multiple Choice

What is the molarity of a NaOH solution if 11.6 mL of 3 M HCl was used to neutralize 25 mL of NaOH?

• 1.392 M

• 0.155 M

• 0.718 M