Chemical Reactions and Types

Study Notes

A chemical reaction is a process in which one or more substances (reactants) are converted into new substances (products)
Chemical reactions involve the transformation of atoms or molecules, resulting in a change in the chemical composition of the substances involved

Synthesis reaction: two or more substances combine to form a new substance
- Example: 2H2 + O2 → 2H2O
Decomposition reaction: a single substance breaks down into two or more simpler substances
- Example: 2H2O → 2H2 + O2
Single displacement reaction: one element displaces another element from a compound
- Example: Zn + CuSO4 → ZnSO4 + Cu
Double displacement reaction: two compounds exchange partners, resulting in the formation of two new compounds
- Example: NaCl + AgNO3 → NaNO3 + AgCl

A chemical equation is a symbolic representation of a chemical reaction, using chemical formulas and symbols to represent the reactants and products
Chemical equations must be balanced, meaning that the number of atoms of each element is the same on both the reactant and product sides

Use chemical formulas to represent the reactants and products
Use arrows to indicate the direction of the reaction (→)
Use coefficients to balance the equation, if necessary
Write the reactants on the left side of the arrow and the products on the right side
Use state symbols to indicate the physical state of the substances (s, l, g, aq)

Count the number of atoms of each element on both the reactant and product sides
Add coefficients to balance the equation, if necessary
Check to ensure that the equation is balanced by counting the number of atoms of each element on both sides

Stoichiometry is the study of the quantitative relationships between reactants and products in a chemical reaction
Mole ratios can be used to determine the amounts of reactants required or products formed in a reaction

Chemical reactions involve the transformation of atoms or molecules, resulting in a change in the chemical composition of the substances involved
Reactants are converted into new substances, known as products

Synthesis reaction: combines two or more substances to form a new substance, e.g., 2H2 + O2 → 2H2O
Decomposition reaction: breaks down a single substance into two or more simpler substances, e.g., 2H2O → 2H2 + O2
Single displacement reaction: one element displaces another element from a compound, e.g., Zn + CuSO4 → ZnSO4 + Cu
Double displacement reaction: two compounds exchange partners, resulting in the formation of two new compounds, e.g., NaCl + AgNO3 → NaNO3 + AgCl

A chemical equation is a symbolic representation of a chemical reaction, using chemical formulas and symbols
Chemical equations must be balanced, meaning that the number of atoms of each element is the same on both the reactant and product sides

Use chemical formulas to represent reactants and products
Use arrows to indicate the direction of the reaction (→)
Use coefficients to balance the equation, if necessary
Reactants are written on the left side of the arrow, and products on the right side
Use state symbols to indicate the physical state of substances (s, l, g, aq)

Count the number of atoms of each element on both reactant and product sides
Add coefficients to balance the equation, if necessary
Ensure the equation is balanced by counting the number of atoms of each element on both sides

Stoichiometry is the study of quantitative relationships between reactants and products in a chemical reaction
Mole ratios can be used to determine the amounts of reactants required or products formed in a reaction