Which statement best describes what the density of an object represents?
Density is the mass of an object per unit of
length.
Density is the volume of an object of a
certain mass.
Density is the length of an object for a certain
mass.
Density is the amount of matter in a certain
volume.

When the chemicals iron sulfide (fes) and hydrochloric acid (hcl) are combined, bubbles appear from the mixture. 1. does the appearance of bubbles indicate a physical or chemical change? 2. why do the bubbles indicate this change? 3. what property is this?

4. propanol and isopropanol are isomers. this means that they have a) the same molecular formula but different chemical properties. b) different molecular formulas but the same chemical properties. c) the same molecular formula and the same chemical properties. d) the same molecular formula but represent different states of the compound

How can parts of a solution be separated by chromatography?