Momentum is a property of an object, but it is different than a physical or chemical property, such as boiling point or flammability. how is momentum different?

Well, momentum is defined as mass times acceleration. As far as I know it is independent of temperature, pressure, and chemical reaction. If you've got 1kg of anything moving at 1m/s you've got a momentum of 1kg m/s, regardless. Or at least you do in low speed newtonian classical physics.

Protons have a positive charge and, collectively, give an element its atomic number.

The answer would be a) -80of