5.00 mL of 3.54*10-4 M Brilliant Blue FCF (FD&C Blue , erioglaucine) blue dye was pipetted into a 250.00 mL volumetric flask and filled to the line with deionized water. Calculate the concentration of dye in this flask.

We can observe physical properties of elements and compounds without changing the substance.

Examples of physical properties: Density, color, boiling point, state of matter, appearance: dull or shiny, etc. 

But we can also observe and measure chemical properties by reacting a substance with something else. For example, like mixing baking soda and vinegar together. The vinegar reacts with the baking soda and produces carbon dioxide: a new substance. 

Some examples of chemical properties: Flammability, amount of heat that is released during combustion, toxicity (how much damage it causes to other organisms), radioactivity, and ability to oxidize (when you have metal that becomes rusty looking).