I was looking for something like Bloomfield's "How things work" but for chemistry rather than physics. Audience is high school kids in a first chemistry course.
A physical change is a change in the physical properties of a substance, such as size, shape, or state, without changing its chemical composition. A chemical change, on the other hand, results in the formation of new substances with different chemical properties.
Elements combine through chemical reactions, in which their atoms bond together to form new molecules with unique properties. This process is governed by the valence electrons of the elements involved.
Energy is required to break the bonds between atoms in a chemical reaction. This energy is then released when new bonds are formed. The overall energy change in a reaction determines if it is exothermic (releases energy) or endothermic (absorbs energy).
The periodic table is a chart that organizes all known elements according to their atomic structure and properties. It is important in chemistry because it allows scientists to predict the chemical behavior of elements and their compounds, and to identify patterns and trends in their properties.
pH is a measure of the acidity or basicity of a solution, which can greatly influence the rate and direction of a chemical reaction. For example, enzymes, which are important catalysts in biological reactions, function best within specific pH ranges. Additionally, the pH of a solution can impact the solubility and reactivity of certain substances.