Question

Translate the following statement into the chemical equation and the balance the equation.
-Phosphorus burns in oxygen to give phosphorus pentoxide.

Answer 1

The process of burning of a material or a substance involves the exposure of that material to gaseous oxygen, which exists in diatomic form. Translation of a statement, into the form of chemical equation involves identification of the symbols of each of the elements involved in the equation, and then balancing the equation involves a series of steps where the final form would have equal number of atoms of each element on both the sides of the equation.

Complete solution:
In order to write a balanced chemical equation, there are a set of rules which we are supposed to follow, those are given below.
At the beginning of the process we determine the correct chemical formulas of the respective elements with which we will denote each product and reactant.
Now we would write the skeleton equation, which indicates the unbalanced chemical equation.
Then we would count the number of atoms of each of the elements which appear in the form of product as well as reactant.
Now finally we would balance every element involved in the reaction, one at a time simply by putting coefficients in front of the formulas.
Then we would make sure that all coefficients which were written, are present in the lowest possible ratio. And if necessary, reduce them to the lowest ratio.
Now if we consider the question, the chemical equation representing burning of phosphorus in order to give phosphorus pentoxide is asked. We know that phosphorus is represented by the symbol $P$ and burning involves exposure to oxygen gas, which is denoted by ${{O}_{2}}$, the subscript signifies number of atoms involved in the gaseous molecule.
Now we would write the unbalanced chemical equation, for burning of phosphorus,
$P+{{O}_{2}}\to {{P}_{2}}{{O}_{5}}$
Now in order to balance the chemical equation we will count the number of atoms, of each element present in each side of the equation. We can see that the oxygen atom on the right hand side are $5$ and on the left hand side there are only $2$. So, we will use the coefficient $5$ on the left hand side and $2$ on the right hand side, so the number of oxygen atoms become $10$ on both sides.
$P+5{{O}_{2}}\to 2{{P}_{2}}{{O}_{5}}$
Now we would balance the number of phosphorus atoms in a similar way, we would just add a coefficient $4$ on the left hand side of the equation.
$4P+5{{O}_{2}}\to 2{{P}_{2}}{{O}_{5}}$

Which is the final balanced chemical equation.

Note: The process of balancing a chemical equation works in a stepwise manner. At first we write the symbols of the element which are reacting with each other, and the product which is formed by that, in a raw format, meaning without any coefficients. Then we add the coefficients on both sides to balance out the number of atoms of each individual element.