Density can be defined in terms of the mass of a substance present in a certain volume.
i.e. Density = Mass/ volume
It helps classify and identify matter due to the following reasons:
1) Density is an intensive property. For a given substance the density will remain the same irrespective of the amount in which it is present.
For example: The density of Aluminum (Al) = 2.7 g/cm3. This value is a constant at a certain temperature and pressure. Therefore, the density will remain the same for 1 kilogram or 1 mg of Al
2) Different elements/compounds have different values of densities which is characteristic of that substance
In the lake that the rivers lead, water molecules evaporate into the sky and form clouds. In the sky, these water droplets condense and form clouds that will eventually rain.
D. precision. At first glance you can mark out A and B because the answers does not relate to the question. If question had said "what do you call it when the measurement is close to the actual answer" then you would have picked C. So that leaves you D. precision.
Yes and no because it's important for a citizen to have a grasp on chemistry but you do not need it to be a politician
