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Chemical Reactions
A chemical reaction occurs when the atoms separate, come together, or rearrange themselves to form new substances with new properties.
Reaction Indicators
When a gas forms it usually indicates that a chemical reaction took place. A chemical reaction can release heat or light and a precipitate or a solid. A chemical reaction can also be seen in rust, tarnishing, and carbonated drinks.
Molecules - Atoms that combine with other atoms to form larger units.
Compound - Two elements chemically combine to form a new substance totally different from the elements that make up the compound.
All compounds are molecules but not all molecules are compounds. Compounds are made up of molecules. But molecules are made up of only one type of atom. Example: O2, Cl2. Compound examples: H2O, NaCl.
Molecules - Atoms that combine with other atoms to form larger units.
Compound - Two elements chemically combine to form a new substance totally different from the elements that make up the compound.
All compounds are molecules but not all molecules are compounds. Compounds are made up of molecules. But molecules are made up of only one type of atom. Example: O2, Cl2. Compound examples: H2O, NaCl.
Stoichiometry
CH4 + 2O2 = CO2 + 2H2O CH4 + O2 = C02 + H2O
N2 + 3H2 = 2NH3 N2 + H2 = NH3
2HCl + Ca(OH)2 = CaCl2 + 2H20 HCl + Ca(OH)2 = CaCl2 + H20
N2 + 3H2 = 2NH3 N2 + H2 = NH3
2HCl + Ca(OH)2 = CaCl2 + 2H20 HCl + Ca(OH)2 = CaCl2 + H20