Chemical Reactions

Chemical reactions occur when two or more substances interact to form new substances with different properties. This process involves the breaking and forming of chemical bonds between atoms. There are several types of chemical reactions, including synthesis, decomposition, single replacement, double replacement, and combustion.

Key Concepts

  1. Chemical Equations:Chemical reactions are represented using chemical equations, which show the reactants and products involved in the reaction. For example, the chemical equation for the reaction between hydrogen and oxygen to form water is: 2H2 + O2 → 2H2O.
  2. Reactants and Products:Reactants are the substances that participate in the reaction, while products are the new substances formed as a result of the reaction.
  3. Law of Conservation of Mass: This law states that matter can neither be created nor destroyed in a chemical reaction. Therefore, the total mass of the reactants must equal the total mass of the products.
  4. Types of Reactions: Different types of chemical reactions include synthesis (combination), decomposition, single replacement, double replacement, and combustion reactions.

Study Guide

Here are some key points to remember when studying chemical reactions:

  1. Understand the difference between reactants and products in a chemical reaction.
  2. Be able to balance chemical equations to satisfy the law of conservation of mass.
  3. Identify the different types of chemical reactions and their characteristics.
  4. Practice writing and interpreting chemical equations for various reactions.

It's important to understand the principles of chemical reactions as they are fundamental to many areas of science, including chemistry, biology, and environmental science.

Remember to review the different types of chemical reactions and the rules for balancing chemical equations to solidify your understanding of this topic.

Good luck with your studies!

◂Science Worksheets and Study Guides Eighth Grade. Chemical reactions

The resources above cover the following skills:

Chemistry: Students will use scientific skills and processes to explain the composition, structure, and interactions of matter in order to support the predictability of structure and energy transformations.

Conservation of Matter: Provide evidence to support the fact that the idea of atoms explains conservation of matter.

Cite evidence from investigations that the total mass of a system remains the same throughout a chemical reaction because the number of atoms of each element remains the same.

Give reasons to justify the statement, 'If the number of atoms stays the same no matter how the same atoms are rearranged, then their total mass stays the same.'

Physical and Chemical Changes: Provide evidence to support the fact that common substances have the ability to change into new substances.

Investigate and describe the occurrence of chemical reactions using the following evidence: Color change; Formation of a precipitate or gas; Release of heat or light.

Use evidence from observations to identify and describe factors that influence reaction rates: Change in temperature; Acidity.

Identify the reactants and products involved in a chemical reaction given a symbolic equation, a word equation, or a description of the reaction.

Provide data from investigations to support the fact that energy is transformed during chemical reactions.