A chemical equation is composed of chemical formulas of the reactants -the reacting substances and the chemical formula of the products- the substances created during the chemical reaction. The two are alienated by an arrow symbol which is normally read as “yields” and every individual substance’s chemical formula is alienated from the rest by a plus sign.
For an example, the equation for the reaction of hydrochloric acid with sodium can be shown as:
2 HCl + 2 Na → 2 NaCl + H2
It is highly crucial for a chemist to be capable of writing accurate balanced equations and to interpret equations written by others. It is also extremely useful for him or her to be aware of the way to foretell the products of some specific types of reactions.
A Chemical Equation shows:
- The reactants which combine together in the reaction.
The products which are created by the reaction.
The amounts of every substance used and every substance formed.
Two significant principles to bear in mind when writing a chemical equation:
- Every chemical compound has a formula which cannot be changed.
A chemical equation gives account of all the atoms used in the chemical reaction. This is an application of the Law of Conservation of Matter. It states that in a chemical reaction atoms are neither created nor destroyed.
C. A few things to bear in mind about writing equations:
The diatomic elements when they stand alone are always written as H2, N2, O2, F2, Cl2, Br2 and I2
The sign, →, is used to denote “yields” and illustrates the direction of the action.
A minute delta, ( ), on top of the arrow illustrates that heat has been supplied.
A double arrow, ↔, illustrates that the reaction is reversible and can move in both directions.
Before starting to balance an equation, crosscheck every one of formulas to ensure that they are right. You must never alter a formula all through the balancing of an equation.
Balancing of an equation is done by putting coefficients in front of the formulas to make sure you have got equivalent number of atoms of everyone of the element on the two sides of the arrow.