CHEMISTRY CLASS ON HOW TO BLANCE A CHEMICAL EQUATION

1. Lesson 3: Oxidation State +
Chemical Equations

2. Recap

3. Balancing a
Chemical
Equation
Steps to Balance a Chemical Equation:
Step 1: Coefficients Versus Subscripts. Understand the
difference between coefficients and indices
Step 2: Sum the Atoms on each side
Step 3: Balance the First Element
Step 4: Repeat for the Other Elements.

4. (Reactants)
(Products)

8. 1. NaOH + HCl --> NaCl + H2O
2. K2O + H2O --> KOH
3. Fe(OH)2 --> FeO + H2O
4. Fe + HCl --> FeCl2 + H2
5. Al(OH)3 --> Al2O3 + H2O
6. Fe(OH)2 + H2O + O2 --> Fe(OH)3
Small Tip: Use a pencil
when you balance on
paper/notebook,
because sometimes
making mistakes is
inevitable
Tip 2: If on one side,
there’s an odd number
of atoms of one element,
while on the other its
even, try starting form
that element

9. Practice Exercises

11. Classes os
Compounds:
Oxides
Examples of
Oxides:
H2O
CO2
CO
SiO2

12. Oxides: Generally classified into 4 groups:
Acidic oxides, Basic oxides, Amphoteric oxides and
Neutral oxides.

14. How to name oxides? Naming Practice:
Na2O
Al2O3
CO2
CO
Copper (II) oxide
Fe (III) oxide
Potassium oxide
Carbon Dioxide
Try Naming: Try Writing
the Formula:

18. Practice Problems:
Main Types of Problems:
1. Write the Chemical Formula of an Oxide
2. Write the formula of an oxide and calculate its molar mass
3. Find the weight percent of an element from the formula
4. Find the Chemical Formula from the weight % (массовая доля)
5. Write the reaction of …oxide with ….