Which option is an example of a physical property?

This question is incomplete, so here is the complete question:

Which option is an example of a physical property? a. toxicity b. flammability c.pH d. freezing point

The correct answer is option d. freezing point.

Explanation:

A physical property is any that can be observed or measured without causing any change in the composition of matter, and thus we can be able to describe it.

In this category we can observe texture, color, smell, density, etc.

Each matter has three states: liquid, solid and gaseous, and all matter can exist in each of them.

The boiling point and the melting point are related to these changes in matter, as well as the freezing point.

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.

molecules are free to separate from each other and will take on the shape of the container. molecules move completely at random and high speeds. they vibrate in a fixed position and do not move around much. molecules expand to the edge of their container.