midterm2

The fundamental principle of volumetric titration involves:

• a) Gravimetric analysis of a precipitate formed in a reaction

• b) Measuring the change in temperature during a reaction

• c) Determining the unknown concentration of a solution by measuring the volume of another solution of known concentration that reacts with it completely.

• d) Using a color change to identify the presence of a specific element.

How is the endpoint of a titration typically detected?

• a) By a significant change in temperature

• b) Through the formation of a gas evolution

• c) Using a chemical indicator that changes color at the equivalence point.

• d) By measuring the electrical conductivity of the solution.

 Iodometry is a type of titration that involves:

• a) Directly titrating a reducing agent with a standard iodine solution

   

• b) Titrating a standard iodine solution with a known concentration of an oxidizing agent

   

• c) Titrating the iodine liberated in a reaction with a standard sodium thiosulfate solution

• d) Measuring the electrical conductivity of a solution to determine its concentration

   

Why is potassium iodide (KI) often added to the solution being titrated in iodometry?

• a) To act as a primary standard

• b) To remove interfering substances

• c) To increase the solubility of iodine (I₂) by forming the triiodide ion (I₃)

• d) To change the color of the solution at the endpoint

 Which of the following statements about the endpoint in manganometry is most accurate?

• a) The solution turns a faint yellow at the endpoint.

• b) A white precipitate forms at the endpoint.

• c) A persistent faint pink color indicates the endpoint.

• d) The solution becomes colorless at the endpoint.

 Complexometry titration relies on the formation of:

• a) A precipitate between the analyte and a precipitating agent

• b) A redox reaction between the analyte and the titrant

• c) Stable coordination complexes between the analyte and the titrant

• d) An acid-base reaction between the analyte and the titrant

 What is the key measurement made in a titrimetric analysis?

• a) The mass of the unknown solution

• b) The temperature changes during the reaction

• c) The volume of the titrant solution used to reach the endpoint

• d) The color intensity of the solution at the endpoint

What is the solution with a known concentration used in a titration called?

• c) Titrant

• a) Analyte

• b) Precipitate

• d) Indicator

 In iodimetry, the analyte (unknown) reacts with excess:

• a) Sodium thiosulfate (Na₂S₂O₃)

• b) Potassium iodide (KI) 

• c) Iodine (I₂) 

• d) Starch indicator

What type of indicator is typically used to detect the endpoint in iodimetry titration?

• a) Universal indicator

• b) Phenolphthalein

• c) Methyl orange

• d) Starch indicator