Purity and Formulations

Question 1

What is the chemical definition of a pure substance?

Answer 1

Something that only contains one compound or element throughout, not mixed with anything else.

Question 2

How can you test the purity of a substance?

Answer 2

By measuring it’s boiling or melting point and comparing it with that of the pure substance.

Question 3

What can impurities in a sample do to its melting and boiling points?

Answer 3

They will lower the melting point and increase the melting range of the substance.

They will also increase the boiling point and may result in the sample boiling over a range or temperatures.

Question 4

What is a formulation and what is specific about its components?

Answer 4

A formula is a useful mixture with a precise purpose that is made by following a formula (recipe).

Each component is a measured quantity and contributes to the properties of the formulation so that it meets its required function.

Question 5

Name two uses of formulations.

Answer 5

1) In the pharmaceutical industry
- altering the formulation of a pill so it delivers the drug to the correct part of the body at the right concentration
- also that it is consumable and has a long enough shelf life
2) In everyday life
- fuels, food and drink, metal alloys, cosmetics, cleaning products, fertilisers etc.
3) Information about a product’s composition