A chemical reaction involves the breaking and forming of chemical bonds between atoms, resulting in the formation of new substances with different properties. In contrast, a physical change does not involve a change in the fundamental chemical structure of the substances involved, it only alters their physical state or appearance.
The Law of Conservation of Mass states that matter cannot be created or destroyed in a chemical reaction, only rearranged. Therefore, when balancing a chemical equation, the number of atoms of each element on the reactant side must be equal to the number of atoms of each element on the product side.
The mole is a unit of measurement used to quantify the amount of a substance in a chemical reaction. It allows chemists to compare and calculate the quantities of different substances involved in a reaction, as well as to determine the empirical and molecular formulas of compounds.
Boyle's Law states that, at a constant temperature, the pressure of a gas is inversely proportional to its volume. Charles's Law states that, at a constant pressure, the volume of a gas is directly proportional to its temperature. Gay-Lussac's Law states that, at a constant volume, the pressure of a gas is directly proportional to its temperature. Together, these laws make up the Ideal Gas Law, which describes the behavior of gases under different conditions.
The four main types of chemical reactions are synthesis, decomposition, single replacement, and double replacement. In a synthesis reaction, two or more substances combine to form a more complex compound. In a decomposition reaction, a compound breaks down into simpler substances. In a single replacement reaction, an element replaces another element in a compound. In a double replacement reaction, the positive and negative ions of two compounds switch places to form two new compounds.