Bellringer 3. 12. 2013

Balance the following equations:

1. ____ C + _____H2 →_____ CH4

2. ___ Na +____ Br2 → ___NaBr

Test: Thursday 3.14

• Review:

• Evidence a chemical reaction has taken place

• Reactants vs products• Coefficients, subscripts, etc.• 4 types of chemical reactions• Balancing chemical equations

Evidence of chemical reaction

• Precipitate is formed: a solid that forms as a result of chemical reaction

• Color change

• Gas is produced: bubbles form

• Odor

Type of Reaction

Definition Equation

Synthesis

Decomposition

Single Replacement

Double Replacement

TYPES OF CHEMICAL REACTIONS:

A = Red B = Blue C = Green D = Yellow

A + B → AB

AB → A + B

AB + C → AC + B

AB + CD → AC + BD

Two or more elements or compounds combine to make a more complex

substance

Compounds break down into simpler substances

Occurs when one element replaces another one in a

compound

Occurs when different atoms in two different

compounds trade places

Identifying Chemical Reactions

1. ____ P + O2 → P4O10

2. ____ BaCl2   +   Na2 SO4 →     NaCl   +   BaSO4

3. ____ Al2O3 → Al + O2

4. ____ Cl2 + NaBr → NaCl + Br2

S = Synthesis D = Decomposition SR = Single Replacement DR = Double Replacement

 

Balancing Equations

____ C + _____H2 →_____ CH4

Use coefficients, can’t change subscripts

Reactants Products