I apologise in advance because I know this is so obvious to most people but......when you are asked to describe the properties of something, what exactly is meant by this?
A 'property' in this sense is a 'characteristic' or 'quality'. Here is a sentence I lifted from a scientific web-page...
"One of the properties of water is its reluctance to condense or crystalize without some nucleii present for that purpose."
That describes one aspect or characteristic of water.