CORE CONCEPTS & CONNECTIONS – 8 th GRADE ADVANCED PHYSICAL SCIENCE

4.1 Identify evidence supporting the law of conservation of matter (11 EQT Questions). Balancing simple chemical equations by adjusting coefficients Gizmo – Chemical Equations ChembalancerGizmo – Chemical Equations Chembalancer Counting the number of atoms of each element present when given a simple chemical formula Stating what a reactant is Stating what a product is Stating what an arrow represents (yields/produces) Differentiating between physical and chemical changes with examples Recognize symbols (g) gas, (s) solid, (aq) aqueous, and (l) liquid. Recognize Avogadro’s number and how it relates to moles and atomic mass. Recognize how the mole relates to chemical equations. Connection to the PAST The Law of Conservation of Mass (or Matter) in a chemical reaction can be stated as: “In a chemical reaction, matter is neither created nor destroyed”. Antoine Laurent Lavoisier’s work in 1785 led to this law. Implications on FUTURE The Theory of Relativity, E=mc 2, explains conversion of mass into energy. This is used to lay the groundwork for the physics that made the development of atomic theories possible.

Connection to the PAST The Law of Conservation of Mass (or Matter) in a chemical reaction can be stated as: “In a chemical reaction, matter is neither created nor destroyed”. Antoine Laurent Lavoisier’s work in 1785 led to this law.

Connection to NOW Today, this law is stated as: The mass of substances produced (products) by a chemical reaction is always equal to the mass of the reacting substances (reactants).

Implications on FUTURE The Theory of Relativity, E=mc 2, explains conversion of mass into energy. This is used to lay the groundwork for the physics that made the development of atomic theories possible.

Core concept The law of conservation of mass (matter) states that mass is neither created nor destroyed in ordinary chemical and physical changes. During a chemical reaction in a closed system, the total mass of the system remains the same. In chemical reactions, the total mass is conserved. Substances react chemically in characteristic ways with other substances to form new substances (compounds) with different characteristic properties. Substances often are placed in categories or groups if they react in similar ways; metals are an example of such a group.

Core concept In a chemical reaction the total mass is conserved. If the number of atoms stays the same no matter how they are rearranged, then their total mass stays the same. Avogadro’s number = 1 mole = the atomic mass In a chemical equation, the coefficients represent numbers of moles of each reactant and product.

Core Concepts A physical change occurs when matter changes from one form to another form without a change in chemical properties. For example, folding paper, tearing paper, boiling water, melting ice, and sharpening a pencil are physical changes. A chemical change occurs when one or more new substances are created in a reaction. The products have new properties. For example, hydrogen and oxygen forming water, baking a cake, cooking an egg, and burning a piece of paper are chemical changes.

Vocabulary Mass, chemical reaction, compound mass symbol reactant formula product subscript coefficient chemical change physical change yield sign mole Avogadro’s number

CORE CONCEPTS & CONNECTIONS – 8 th GRADE ADVANCED PHYSICAL SCIENCE 4.0 Conduct investigations and utilize appropriate tools, technologies, and teamwork to build an understanding of chemical interactions Identify the types of reactions (7 EQT Questions)

Connection to the PAST The Law of Conservation of Mass (or Matter) in a chemical reaction can be stated as: “In a chemical reaction, matter is neither created nor destroyed”. Antoine Laurent Lavoisier’s work in 1785 led to this law.

Connection to NOW Today, this law is stated as: The mass of substances produced (products) by a chemical reaction is always equal to the mass of the reacting substances (reactants).

Implications on FUTURE The Theory of Relativity, E=mc 2, explains conversion of mass into energy. This is used to lay the groundwork for the physics that made the development of atomic theories possible.

Core concept Many reactions are grouped into one of four categories. A synthesis reaction is a reaction in which two or more substances combine to form a single compound. A decomposition reaction is a reaction in which a single compound breaks down to form two or more simpler substances. A single replacement reaction is a reaction in which an element takes the place of another element that is part of a compound. A double replacement reaction is a reaction in which ions in two compounds switch places. Combustion is a reaction between a fuel (organic) in the presence of oxygen and an initial starter of energy (heat) forming carbon dioxide + water and energy (heat or light) SynthesisA + B  AB DecompositionAB  A + B Single Replacement (single displacement)A + BC  AC + B Double Replacement (double displacement)AB + CD  AD + CB Combustion Ex: CH 4 + 2O 2 → CO 2 + 2H 2 O + energy

Vocabulary synthesis reaction, decomposition reaction, single replacement reaction, double replacement reaction, Combustion