Hello, reders welcome to chemwhite.com today we will explain about chemical equation and representation of chemical equation.

Read MoreWhat is valence electrons?

What is chemical equation?

A chemical equation is one type of equation in which it represent in the form of symbols and formulae. and direction of chemical reaction and physical state of chemical of the reacting are also represented by symbols.


• Reactant – it represent on the left hand side.

• Products – it represent on the right hand side.

lets know with examples,

Repersentation of Direction of Chemical Equation

1. Net Forwarded reaction in chemical reaction the symbol is,

2. The state of chemical equilibrium in chemical reaction, the symbol is

3. Stoichiometric relationship, the symbols.

4. A reaction that occur in both forward and backward direction, the symbol is,

Repersentation of physical state of chemical reaction

  1. Solid (s) – solid state.
  2. Liquid (l) – liquid state.
  3. Gas (g) – gaseous.
  4. Aqueous (aq) – aqueous solution.

Types of chemical reaction

  1. Combination reaction
  2. Decomposition reaction
  3. Displacement reaction
  4. Double displacement reaction
  5. Redox
Combination reaction

In this reaction, combination of two compound to form single compound.

for examples,

A + B – AB

H2 + O2 – H2O

2Mg + O2 – 2MgO

CO + O2 – CO2

Decomposition reaction

In this reaction, involves breakdown of a compound into different compounds. example of these type of reaction are,

for examples,

H2O – 2H2 + O2

Agcl – 2Ag + Cl2

Displacement reaction

for examples,

A + BC – AC + B

In this reaction, A is more reactive then B. According to this, A is displace to B. it can displace it. Due to this product is AC + B.

lets take one examples,

Zn + 2HCI – ZnCl2 + H2

According to this reaction zn have more reactive then H. it mean, Zn are displace hydrogen. finely, it gives ZnCI + H2 as a product.

Double displacement reaction

In case of double displacement reaction, two compound react an exchange of ions to form two new compound are called double displacement reaction.

In this reaction, the positive ions exchange negative ions partners. it represent bye the general equation.

for examples,

AB + CD – AD + CB

in this of double displacement reaction, the main concept are two compound and product are two different compound.


If the hydrogen and fluorine react together then hydrogen is oxidized whereas fluorine is reduced. the reaction can be written as,

H2 + F2 – 2HF

According to this reaction, hydrogen fluorine is formed as a product.

Reactivity series of Non – metals

  1. F – Fluorine
  2. CI – Chlorine
  3. Br – Bromine
  4. I – iodine

These are reactivity series of non – metals.

Reactivity series of metals

  1. K – Potassium
  2. Na – Sodium
  3. CO – Calsium
  4. Mg – magnesium
  5. Al – Aluminium
  6. Zn – Zinc
  7. Fe – Iron
  8. Sn – Tin
  9. Pb – Lead
  10. H – Hydrogen
  11. Cu – Copper
  12. Hg – Mercury
  13. Ag – Silver
  14. Pt – Platinum
  15. Au – Gold

These are all reactivity of metals.

Question and Answer

1. What are difference between oxidation and reduction?


  1. Adition of oxygen.
  2. Removel of hydrogen.
  3. Adition of non-metals Or electronegative elements.
  4. Removel of metals or electropositive elements.
  5. Loss of electrons.


  1. Addition of hydrogen.
  2. Removel of oxygen.
  3. Addition of metals or electropositive elements.
  4. Removals of non – metals or electronegative elements.
  5. Gain of electrons.

2. What are reactant and product in a chemical equation?

If you want to do chemical reaction, first you will know in a chemical equation, the reactant are any substance, or compound, both reactant are in left side of the arrow. the product are any new substance or compound (different from reactant) that were produced during the reaction. In a chemical reaction, they (product) go on the right side of the arrow.

for examples,

2H2 + O2 (reactant) – 2H2O (product)

In chemical reaction, reactant represent left side of arrow and product represent right side of arrow as show on the reaction.


Leave a Reply

Avatar placeholder

Your email address will not be published.