Explain one negative externality that could occur due to the building of a new airport (2 marks)

This question tests the student's knowledge on the topic of negative externalities while also inviting them to think of its application in the real world.

The buiding of a new airport is a common theme in Economics papers, both A-level and GCSE due to the current talks of expanding Heathrow Airport. 

It's best to start answering the question with a definition of negative externalities: Negative externalities are the costs suffered by a third party as a result of an economic transaction, given that the third party wasn't part of the transaction. Secondly, we have to given an example of a negative externality: pollution is the most common one. Transporting building materials creates CO2 and the implied running of airplanes to and from the new airport pollute the air. Therefore, the whole population who is enjoying clean air will suffer.