A laboratory prepares a liquid containing three hydrocarbons, P, Q and R.
| Hydrocarbon | Boiling point in °C |
|---|---|
| P | 69 |
| Q | 98 |
| R | 126 |
The liquid is heated to 110 °C.
Explain why the liquid is a mixture and which hydrocarbons will have boiled when the temperature reaches 110 °C.