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CHEMICAL REACTIONS
TOPICS:
 Identifying the parts of chemical reactions
 Writing chemical equations from word equations
 Identify and include physical states in chemical equations
 Identifying the seven diatomic elements
 Writing chemical formulas
Standards Addressed:
Conservation of Matter and Stoichiometry
3a. Students know how to describe chemical reactions by writing balanced equations
Anticipatory Set: Get the students’ attention/interest
 What do react to? Or are you the non-reactive type?
 Parent + nagging → Me annoyed
Objective:
By the end of the lesson, the student will be able to:
 Identifying the reactants, products and other parts of chemical equations
 Write word equations from a chemical reaction description
 Write chemical equations from word equations
 Identify and include solid (s), liquid (l), gas (s), and/or aqueous (aq) in chemical equations
 Identify and write the seven diatomic elements
Purpose: Reason doing lesson.
 We will use this information to write and balance chemical equation
 You will be tested on this information in the spring.
Teacher Input
VOCAB
1. Chemical equation: a precise detailed accounting of both the identities and amounts
of reactants consumed and products formed in a reaction
 Identities: all participants in reaction get named
 Amounts: how much is specified in equation, (moles)
 Reactants: what you start with
 Products: what is made
2. Word equation: description of the reaction without using formulas
3. Reactants: the starting substance(s) in a chemical reaction
4. Product: substance(s) formed in a chemical reaction
5. Catalyst: a substance that speeds up a reaction without being used up; enzymes
good example
6. Diatomic: two of the same atom naturally bound together
7. Aqueous: dissolved in water
NOTES: All ionic compounds exist as solids
CH4= methane gas
NH3= ammonia
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To write word equations:
I will give you a description of what’s happening and you the write word equation
Water-you all know water, seen heard taste. Write down the word equation for:
o
hydrogen reacts with oxygen to form water
*Remember the 7 diatomic elements: Hydrogen and Oxygen and some others exist bound together. They are
always found as a pair in their elemental form, so when you write them write them as H2, O2.
Words indicating reactants:
Words indicating products:
(CFU & GP) WRITE WORD EQUATIONS FOR THE FOLLOWING DESCRIPTIONS:
o
Calcium metal reacts with chlorine gas to produce calcium chloride

When zinc metal reacts with oxygen gas, solid zinc oxide is formed.

Carbon dioxide and water are produced when methane gas is burned in oxygen.

When zinc metal is placed in a solution of hydrochloric acid (HCl), hydrogen gas and a zinc
chloride solution are formed.
Rules for balancing:
1. Must have same # of each atom on both sides of the equation
2. Must use coefficients to balance, can not add subscripts. Once you get the correct formula,
do not change it. If you add subscripts to the formulas, you have changed the compound.
Now, go back and balance each of the equations
Now, go back and put in physical states
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Independent Practice TUESDAY 11/30
 Worksheet 4A #’s 1-3

 Study for nomenclature quiz on Thursday
 Bring your textbook to class Wednesday and Thursday
Independent Practice- WEDNESDAY 12/1
 Worksheet 4A #’s 4 and 5

 Study for nomenclature quiz on Thursday
 Bring your textbook to class on Thursday
Independent Practice THURSDAY 12/2
 Writing Equations Worksheet
 Finish Lab Pre-Write
Independent Practice MONDAY 12/6
 Balance the equations on worksheet 4A #’s 1-5
Independent Practice TUESDAY 12/7
 Balance the equations on Writing Equations Worksheet
Independent Practice WEDNESDAY 12/8
 Equations Worksheet-word equation, formula equation, and balance
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Worksheet 4A
Descriptions → Balanced Chemical Equations
For each of the following descriptions, write:
 The word equation
 The chemical equation, including physical states (s, l, g, aq)
 The balanced chemical equation
1.Solid aluminum chloride is formed when elemental aluminum is burned in chlorine gas.
2. Water and nitrogen gas are formed from the combustion of hydrogen gas and nitrogen
monoxide gas.
3. Aqueous sodium chloride reacts with aqueous sulfuric acid (H2SO4) to produce a solution of
sodium sulfate and hydrogen chloride gas.
4. When a solution of calcium chloride reacts with a solution of sodium hydroxide, calcium
hydroxide precipitate is formed in a solution of sodium chloride.
5. Barium sulfate precipitate is formed in a solution of sodium nitrate when a solution of barium
nitrate is added to a solution of sodium sulfate.