Rikki has a sample of water but he is not sure if it is pure or not He heats the water until it begins to boil. He records the temperature which is 103^circ C. Is this water pure?

## Step 1:Firstly, we need to remember that the boiling point of pure water under standard conditions is .## Step 2:Next, we compare this boiling point with the temperature that Rikki recorded when he heated his water sample. He recorded a boiling point of . ## Step 3:If Rikki's sample was indeed pure water, it would have boiled at . However, the recorded boiling point is higher than this. Therefore, the water is likely to contain other substances. This makes the sample impure.