CLASS 10 NOTES
SCIENCE
Chemical Reactions &
Equations
PRASHANT KIRAD
, PRASHANT KIRAD
Chemical Reaction:
The transformation of chemical substance into another
chemical substance is known as Chemical Reaction. e.g.:
Rusting of iron, the setting of milk into curd, digestion
of food, respiration, etc.
JOSH METER?
Chemical changes indicate that a chemical reaction has
occurred.
Characteristics of chemical reactions:
Formation of new substances with different
Chemical Equation: properties, Change in color, Evolution of gas,
Representation of chemical Evolution or absorption of heat, Formation of a
precipitate, Irreversibility of many chemical
reaction using symbols and
reactions, Change in state of matter, Change in
formulae of the substances energy.
is called Chemical Equation.
Example: A + B → C + D
D
RA
Reactant Product
Magnesium + Oxygen → Magnesium oxide
Mg + O2→ MgO
KI
Magnesium ribbon burns
T
with a dazzling white
AN
flame and changes into a
white powder. This
powder is magnesium
H
oxide. It is formed due
AS
to the reaction between
magnesium and oxygen
present in the air
PR
Magnesium is rubbed with sandpaper to remove the oxide layer, allowing it to burn more easily.
Balanced Chemical Equation:
A balanced chemical equation has an equal number of atoms of each
element in the reactant and product side.
Law of Conservation of Mass: Mass of reactants = Mass of products.
Fe+H2O→Fe3O4+H2 (Unbalanced)
3Fe+4H2O→Fe 3O4 + 4H 2 (Balanced)
number of atoms of each element in reactants = number of atoms of each
element in products
SCIENCE
Chemical Reactions &
Equations
PRASHANT KIRAD
, PRASHANT KIRAD
Chemical Reaction:
The transformation of chemical substance into another
chemical substance is known as Chemical Reaction. e.g.:
Rusting of iron, the setting of milk into curd, digestion
of food, respiration, etc.
JOSH METER?
Chemical changes indicate that a chemical reaction has
occurred.
Characteristics of chemical reactions:
Formation of new substances with different
Chemical Equation: properties, Change in color, Evolution of gas,
Representation of chemical Evolution or absorption of heat, Formation of a
precipitate, Irreversibility of many chemical
reaction using symbols and
reactions, Change in state of matter, Change in
formulae of the substances energy.
is called Chemical Equation.
Example: A + B → C + D
D
RA
Reactant Product
Magnesium + Oxygen → Magnesium oxide
Mg + O2→ MgO
KI
Magnesium ribbon burns
T
with a dazzling white
AN
flame and changes into a
white powder. This
powder is magnesium
H
oxide. It is formed due
AS
to the reaction between
magnesium and oxygen
present in the air
PR
Magnesium is rubbed with sandpaper to remove the oxide layer, allowing it to burn more easily.
Balanced Chemical Equation:
A balanced chemical equation has an equal number of atoms of each
element in the reactant and product side.
Law of Conservation of Mass: Mass of reactants = Mass of products.
Fe+H2O→Fe3O4+H2 (Unbalanced)
3Fe+4H2O→Fe 3O4 + 4H 2 (Balanced)
number of atoms of each element in reactants = number of atoms of each
element in products
