Hong Yu Lui
Wenzel Chem H
Sep 13th, 2014
Lab report #1 on chemical and physical properties/ changes
The purpose of this experiment is to allow students to understand how to differentiate physical and chemical properties and reactions of matter by observing changes of matters under circumstances. Physical properties are properties of matter that can be observed without changing the composition of the matter, including the volume, mass, color, density, and shape of it. Chemical properties include the matter’s flammability, acidity, and heat of combustion. It can only be observed through a chemical reaction. Chemical reaction is when the chemical identity of a matter is altered through reacting to another matter. There is a change in the arrangement of atoms. A lot of property changes during a chemical reaction too. Chemical reactions are also very hard to reverse. One example of chemical change is when sugar is combined with sulfuric acid. We can tell it is a chemical change because heat and bubbles are produced, and carbon was separated from the other substances. On the other hand, physical reaction only does macroscopic changes to the matter, for example, altering the shape, and painting the matter. There is not rearrangement of atoms in a physical change. Only a few properties change during a physical reaction, and they are mostly easy to reverse. One example of a physical change is mixing salt and water together. Although there is not a change in its appearance as they are all transparent liquids, the mixed salt and water can be easily separated again through boiling the mixture, making it a physical change because it is easily reversible.
1. Homogeneous means similar in kind, composed of the same kinds. Furthermore, homogeneous mixture means that the components of a mixture are evenly distributed and cannot be easily told apart. For example, salad is a homogeneous mixture because we can easily tell the...
Please join StudyMode to read the full document