Titrimetric/Volumetric Analysis Notes

These flashcards cover key concepts in titrimetric and volumetric analysis, focusing on definitions, methods, and important principles discussed during the lecture.

What is the purpose of titrimetric analysis?

To measure the amount of an active constituent in a sample by determining the volume of a solution with a known concentration that reacts with it.

What components comprise titrimetric analysis?

Analyte, titrant, indicator, stoichiometric/equivalence point, end point.

Define analyte in titrimetric analysis.

The chemical substance being analyzed.

What is a titrant?

A solution of known concentration used in titrimetric analysis.

What is the equivalence point in titration?

The theoretical point at which equivalent amounts of analyte and titrant have reacted.

What is the purpose of an indicator in titrimetric analysis?

To signal the end point of the titration by changing color.

Differentiate between direct and indirect titration.

Direct titration involves the standard solution reacting directly with the analyte, whereas indirect titration involves converting the sample to an intermediate product before titrating.

What is a primary standard?

An ultra-pure compound used as a standard for determining concentrations in titrimetric analysis.

What qualities must a primary standard possess?

High purity, atmospheric stability, ease of preparation, water solubility, reacts stoichiometrically, and has a fairly high equivalent weight.

What is the difference between a primary and a secondary standard?

A primary standard is pure with a known concentration; a secondary standard may not be pure, but its exact concentration is known.

What does 1 equivalent of acid react with?

1 equivalent of base.

How do you calculate the gram-equivalent weight?

It is the mass of a substance that reacts with or replaces 1 gram-atom of hydrogen.

What is the theoretical normality in titrimetric analysis?

An approximation of the volume required to complete a reaction, assuming actual and theoretical normality are equal.

What is actual normality?

The exact expression of the concentration of the solute in a solution.

What is the function of a titer value in titrimetric analysis?

It is the weight of a substance in milligrams that is chemically equivalent to 1 mL of standard solution.

What is neutralization in titrimetric analysis?

The chemical process where an acid reacts with a base to produce water and salt.

Name some common acid-base indicators used in neutralization reactions.

Phenolphthalein, methyl red, methyl orange.

What is the Kjeldahl Method used for?

To determine organic nitrogen and protein content in grains or meats.

What does the term 'residual titration' refer to?

Adding an excess of standard solution to a sample, then back-titrating with a second standard solution.

Define oxidation-reduction (redox) reactions in the context of titrimetric analysis.

Reactions involving the transfer of electrons, typically between a sample and a standard solution of an oxidizing or reducing agent.

How can one determine the endpoint of a redox titration?

By using self-indication (if titrant is colored), starch indicator or redox indicators that change color during the reaction.

What are common methods of redox titrations?

Permanganometry, cerimetry, iodimetry, and iodometry.

What is precipitimetry?

A method where a sample is made to react with a precipitating reagent until the endpoint, indicated by precipitation, is reached.

Explain what complexometry involves in volumetric analysis.

It involves titrating a sample to form a complex with a ligand in the presence of an indicator until the endpoint is reached.