Topic 4 Acids and bases Flashcards
What does a pH scale go from
1 - 14
What is the pH scale measure of
How acidic or alkaline solution
What does a low pH mean
The solution is acidic
What does ahigh pH mean
The solution is alkaline
What is a neutral pH
pH 7
What is an indicator
A dye that changes colour depending on whether it is above or below a certain PH

What are wide range indicators
A mixture of dies that means they gradually change colour of a broad range of pH e.g. universal indicator
What are wide range indicators useful for
Estimating the pH of a solution
Why is the universal indicator only an estimate
Colour is subjective
What is a pH probe attached to
A pH meter
What does a pH probe do
Measures pH electronically
How is the pH probe used
Placed in a solution you’re measuring at the pH is given on a digital display as a numerical value meaning it is more accurate than indicator
What do acids and bases do to each other
Neutralise each other
What is an acid
A substance that forms aqueous solutions with a pH of less than seven
Acids form H plus ions in water
What is a base
A substance with a pH greater than seven
