12/4 & 12/5 - 8th Grade Agenda

Learning Objective: Balancing Chemical EquationsCollect HW: Reading & Notetaking: p.114 – 116Collect Signed Grade Printout.Drug Outreach and Education ProgramTextbook Reading p. 235-239HW: Reading & Notetaking p.117 – 118Reminder HW: Science Fair Background due 1/14 & 1/15 (10 Points)

Daily Reflection

• Prompt: Write 3 questions about chemical equations.

What is a Chemical Equation

• Reactant + Reactant Product + Product

• H2 + O2 H2O2

• Subscript shows the number of atoms of an element in a molecule

How many atoms are there?• Water: H2O• Carbon Dioxide:CO2

• Carbon Monoxide: CO• Methane: CH4

• Propane: C3H8

• Sugar: C12H22O11

• Rubbing alcohol: C3H8O• Ammonia: NH3

• Sodium chloride: NaCl• Washing soda: Na2CO3

• Baking soda: NaHCO3.

What is Conservation of Mass?• The total mass of the reactant must equal the

total mass of the products• During a chemical reaction, matter is not

created or destroyed

Open End vs Closed End systems

What is a coefficient

•2H2 + O2 2H2O

• The number in front of a chemical formula in a chemical is called an coefficient

• It tells you how many molecules or atoms of each reactant or product take part in the reaction

What is a Chemical Equation

• Reactant + Reactant Product + Product

• H2 + O2 H2O2

• Subscript shows the number of atoms of an element in a molecule

Balancing Equation

Types of Chemical ReactionsWhat is a Synthesis?

• When two or more substances (elements or compounds) combine to make a more complex substance, the process is called a synthesis

Types of Chemical ReactionsWhat is Decomposition?

• Decomposition reaction breaks down compounds into simpler products

What is a Replacement reaction?

• It is similar to a girl switching boyfriends

• A reaction in which one element replaces another in a compound