L3 Yr1- Recap Titration Vocabulary

In the context of titration, what is the definition of 'Titre'?

• The volume of titrant required to reach the endpoint

• The concentration of the titrant

• The pH level at the endpoint

• The initial volume of the solution

Answer explanation

In titration, 'Titre' refers to the volume of titrant needed to reach the endpoint of the reaction. This is crucial for determining the concentration of the analyte being tested.

A 'Solvent' is a substance that:

• reacts with solutes to form a solution

• dissolves solutes to form a solution

• is always a liquid in chemical reactions

• is the solute in a chemical reaction

Answer explanation

A 'Solvent' is defined as a substance that dissolves solutes to form a solution. This means it facilitates the mixing of solutes, making the second choice the correct answer. The other options are inaccurate descriptions.

A 'Solution' is defined as a homogeneous mixture composed of two or more substances. Which of the following best describes its composition?

• A solution is a heterogeneous mixture of substances.

• A solution is a mixture of a substance dissolved in a liquid.

• A solution is a compound formed by chemical reactions.

• A solution is a pure substance.

Answer explanation

A solution is defined as a homogeneous mixture, meaning its components are evenly distributed. Therefore, the correct choice is that a solution is a homogeneous mixture of substances.

A 'Solute' in a solution is:

• the substance that is dissolved

• the liquid in which the solute is dissolved

• a type of chemical reaction

• a measure of concentration

Answer explanation

A 'solute' is defined as the substance that is dissolved in a solution. In contrast, the solvent is the liquid that dissolves the solute. Therefore, the correct answer is 'the substance that is dissolved'.

A 'Standard Solution' is a solution of known concentration. How is it prepared?

• By dissolving a known mass of solute in a specific volume of solvent

• By mixing two solutions of unknown concentrations

• By diluting a solution with an unknown concentration

• By evaporating the solvent from a solution

Answer explanation

A 'Standard Solution' is prepared by dissolving a known mass of solute in a specific volume of solvent, ensuring the concentration is accurately known. This method is essential for precise measurements in experiments.

In the context of titration, what does 'Expected Value' mean?

• The theoretical value of the titrant needed to reach the endpoint.

• The actual volume of titrant used in the experiment.

• The average value obtained from multiple titration trials.

• The difference between the initial and final readings of the burette.

Answer explanation

In titration, 'Expected Value' refers to the theoretical amount of titrant calculated to reach the endpoint of the reaction. This is crucial for determining the concentration of the analyte.

What is 'Actual Value' and how is it obtained?

• 'Actual Value' is the measurement or result obtained directly from an experiment or observation.

• 'Actual Value' is the historical cost of an asset and is obtained through accounting records.

• 'Actual Value' is the replacement cost of an asset and is obtained through insurance valuation.

• 'Actual Value' is the book value of an asset and is obtained through financial statements.

Answer explanation

In science, the actual value refers to the measurement or result obtained directly from an experiment or observation. It represents the data collected through practical procedures, such as readings from instruments, measurements during experiments, or observed outcomes.

The role of an 'Indicator' in titrations is to:

• change the color of the solution at the endpoint

• react with the titrant

• neutralize the solution

• increase the pH of the solution

Answer explanation

The role of an 'Indicator' in titrations is to change the color of the solution at the endpoint, signaling that the reaction is complete. This visual cue helps determine when to stop adding the titrant.

A 'Strong Acid' is one that completely dissociates in water. Which of the following is an example of a strong acid?

• Hydrochloric acid (HCl)

• Acetic acid (CH3COOH)

• Carbonic acid (H2CO3)

• Phosphoric acid (H3PO4)

Answer explanation

Hydrochloric acid (HCl) is a strong acid because it completely dissociates in water, releasing all of its hydrogen ions. In contrast, acetic acid, carbonic acid, and phosphoric acid are weak acids that do not fully dissociate.

A 'Strong Base' is defined as a base that completely dissociates in solution. Which of the following is an example of a strong base?

• Sodium hydroxide (NaOH)

• Ammonia (NH3)

• Acetic acid (CH3COOH)

• Water (H2O)

Answer explanation

Sodium hydroxide (NaOH) is a strong base because it completely dissociates in solution, releasing hydroxide ions. In contrast, ammonia (NH3) is a weak base, acetic acid (CH3COOH) is an acid, and water (H2O) is neutral.