According to this law, whenever matter undergoes a chemical change or physical change in an enclosed system, the total mass of reacting matter (reactants) is exactly equal to the total mass of the products of the reaction. Hence Lavoisier called this, the law of conservation of mass.

There are five basic laws of chemical combination that govern the chemical combinations of elements:

• Law of Conservation of Mass.
• Law of Definite Proportions.
• Law of Multiple Proportions.
• Gay Lussac’s Law of Gaseous Volumes.
• Avogadro’s Law.

The chemicals can be used for verifying the law of chemical combination is matter.

John Dalton

2) Law of Constant Composition or Definite Proportions It states that “A chemical compound is always found to be made up of the same elements combined together in the same fixed proportion by mass”. For example, a sample of pure water from various sources or any country is always made up of only hydrogen and oxygen.

A chemical combination reaction is a reaction in which two or more elements or compunds combine to form one compound.

Joseph Proust

The law of constant composition says that, in any particular chemical compound, all samples of that compound will be made up of the same elements in the same proportion or ratio. For example, any water molecule is always made up of two hydrogen atoms and one oxygen atom in a 2:1 ratio.

Positive correlation is a relationship between two variables in which both variables move in tandem—that is, in the same direction. A positive correlation exists when one variable decreases as the other variable decreases, or one variable increases while the other increases.