Chemical Equation-Equation Based Problem

Balancing chemical equations is the most critical equation-based problem. This crucial ability is necessary for stoichiometry, reaction analysis, and lab work.

The ultimate objective of balancing chemical reactions is equal atoms per element in both reactants and products. The universal rule of mass conservation states that we cannot create or destroy a matter. So, if we start with 10 oxygen atoms, we must end with ten. Chemical reactions do not affect the basic building blocks of matter but rather their order. Picture a house constructed of blocks to understand this. We can deconstruct the home and create an aeroplane, but the blocks’ colours and shapes remain unchanged.

But how can we solve these equations? It’s only a matter of finding the right coefficients (numbers in front of each molecule). It is advisable to balance the atom that appears the least on one side. Then go on to the next least visible atom and so on. Finally, count each element’s atoms on both sides again.

Equation-based problem examples

P4O10 + H2O → H3PO4

Let us start with the least frequent element. Notably, oxygen appears twice on the left side. Let’s begin using phosphorus instead of hydrogen. The left has four phosphorus atoms, the right has one phosphorus atom. We may place a four on the molecule with phosphorus on the right to balance them.

P4O10 + H2O → 4 H3PO4

Next is hydrogen. We still don’t want to balance oxygen, since more than one molecule is on the left-hand side. Start with molecules that occur just once on each side. So, two hydrogen atoms on the left, twelve on the right. We need to add a six to H2O on the left to balance that.

P4O10 + 6 H2O → 4 H3PO4

We can now check the oxygen balance. On the left are ten oxygen atoms from P4O10 and six from H2O, for a total of 16. So it’s already balanced. The final balanced equation is:

P4O10 + 6 H2O → 4 H3PO4

 CO2 + H2O → C6H12O6 + O2

 Prioritise elements that appear only once on each side of the equation. Carbon and hydrogen both meet these criteria. So, let’s start with Carbon—one carbon atom on the left, six on the right. So we multiply the carbon-containing molecule on the left by six.

6CO2 + H2O → C6H12O6 + O2

Next, consider hydrogen. Two hydrogen atoms left, twelve right. So, we’ll multiply the hydrogen-containing molecule on the left by 6.

6CO2 + 6H2O → C6H12O6 + O2

Check the oxygen now. 18 oxygen molecules (6x2 + 6x1) on the left. 8 Oxygen molecules on the right now have two options: We may multiply C6H12O6 or O2 by a coefficient. Due to the change in carbon and hydrogen atoms in C6H12O6, the coefficients for everything on the left must change. To avoid this, only change the molecule with the fewest elements; in this case, O2. So we may multiply the O2 on the right by 6. Our final answer is:

6CO2 + 6H2O → C6H12O6 + 6O2

Why is Balancing the chemical equations essential?

Each side of the equation must contain an equal number of atoms. Due to the Law of Mass Conservation, it also has to balance.

The rule specifies that both before and after the experiment shall be equal in quantity and quality. Antoine Laurent established this law in 1789, and he found that we cannot create or destroy a matter. Unbalanced equations are not correct equations, and even if they include the exact elements and quantities, they are not accurate. These imbalanced equations are also not used to calculate chemical reactions.

Also, chemical equations must balance since chemicals do not react until the mole ratios are correct. A balanced equation is also necessary to determine the reactant required to make a certain product, and it simply indicates that the proper number of reactants is essential to generate the right products.

Some students struggle with balancing equations. It takes practice, patience, and a good memory. You may have challenges at first, but keep working hard, and you will succeed. You must learn reaction formulas. Understand and balance the concept.

Chemical equation types

Combination or synthesis chemical reaction

In this equation, two to three reactants combine to generate a new product. Example H2 + O2= H2O. In this chemical equation, two hydrogen atoms combine to make water. Hence the name “synthesis reaction”. It is an unequal equation since the reactant has two oxygen atoms while the product has one. But the equation is valid only when atoms and moles are equal, and to balance the equation, use the combustion method.

Decomposition chemical reaction

It happens when one chemical decomposes into two or more. Example :PbNO3 = PbO + NO2 + O2. Lead nitrate decomposes in this equation to nitrogen dioxide, oxygen, and lead oxide.

Displacement or replacement reaction

Single displacement and double displacement are two types of chemical reactions. One molecule exchanges from reactant to product in a single displacement reaction, while two sets of molecule exchange. Single displacement reaction example is XY + Z→  XZ + Y.

In this example, zinc sulphate replaces hydrogen from sulfuric acid. Because of just one cation exchange, this is a single displacement reaction. Using the same example, the second displacement chemical equation is BaCl2 + NaSO4 →  BaSO4 + 2NaCl. It leaves Barium and attaches to Sodium in this equation.

Combustion Reaction

This chemical reaction produces H2O and CO2 from an oxygen and carbon compound. When an organic compound like oxygen burns, it produces water, CO2, or other products. Combustion occurs when any substance combines oxygen.

Acid-base reaction

From acid and base, a simple chemical reaction produces water and salt. This reaction is also known as the neutralisation of acid-base reaction, and these are critical reactions in biological systems.Example , HCl+ NaOH → NaCl +H2O

Conclusion

Write the chemical formulae of the reactants on the left side. Then write the products to the equation. An arrow between the two sides indicates the reaction. The unbalanced data will help you balance the equation.

Now apply mass conservation law. An equation’s both sides must have the same atom number. Finding an element with just one reactant and product is one of the simplest methods of balancing a chemical equation. Once balanced one element, you may go on to the other and keep moving until all elements balance. Place the coefficient in front of chemical formulas to balance the chemical equations.