Module 2 - chapter 4 key terms

Question 1

Strong acid

Answer 1

A strong acid, e.g HCl, releases all its hydrogen atoms into solution as H+ ions and completely dissociates in aqueous solution.

Question 2

Weak acid

Answer 2

A weak acid, e.g ethanoic acid, only releases a small proportion of its available hydrogen atoms into solution as H+ ions. It partially dissociates in aqueous solution.

Question 3

Base

Answer 3

A base neutralises an acid to form a salt.

Question 4

Alkali

Answer 4

An alkali is a base that dissolves in water releasing hydroxide ions (OH-) into the solution.

Question 5

Titration

Answer 5

A technique used to accurately measure the volume the volume of one solution that reacts exactly with another solution.

Question 6

Volumetric flask

Answer 6

Used to make up a standard solution very accurately.

Question 7

End point (of a titration)

Answer 7

The point when the indicator changes colour and the neutralisation has occurred.

Question 8

Oxidation number

Answer 8

based on a set of rules that apply to atoms, and can be thought of as the number of electrons involved in bonding to a different element.

Question 9

Oxidation

Answer 9

Addition of oxygen, loss of electrons or increase In oxidation number.

Question 10

Reduction

Answer 10

Loss of oxygen, gain of electrons or decrease in oxidation number.

Question 11

Redox reactions

Answer 11

They involve reduction and oxidation. If one process happens so must the other - of something is reduced, something else must be oxidised.