What concept is the reason for balancing recations

The Law of conservation of mass is the concept used for balancing reactions.

Explanation:

The balancing of equation is important because the atoms are neither created nor destroyed during a chemical reaction. During the chemical reactions the atoms are never lost or gained they are rearranged. The mass of the reactants should be equal to the mass of the products.

In a chemical reaction the number of atoms for each element in the reaction and the total charge is the same for both reactants and products is known as balancing reaction.

The examples of chemical reaction are rusting of iron, burning of wood and mixing of acid and base.

For example, a balanced equation.

2Fe2O3 + 3C → 4Fe + 3CO2

Fe - 4                Fe - 4

O - 6                 O - 6

C - 3                  C -3

points

explanation:

weight of any object is given by

w = m*g

where m is mass of the object and g is the acceleration due to gravity.

for earth the value of g is 9.8 m/s^2 so

w=117.6 n m=12 g=?

117.6=12g => g=9.8 m/s^2

which is the force of gravity on earth.