Balance the following equation:
K2CrO4+Na2SO3+HCl→KCl+Na2SO4+CrCl3+H2O.
Generally coefficients of 1 are omitted from balanced chemical equations. When entering your answer, include coefficients of 1 as required for grading purposes.
Enter the coefficients for each compound, separated by commas, in the order in which they appear in the equation (e.g., 1,2,3,4,5,6,7).
In the process of oxidizing I− to I2, SO42− is reduced to SO2. How many moles of SO2 are produced in the formation of one mole of I2?
Express your answer numerically in moles.
Concepts and reason
The problem is based on the concept of balancing a chemical equation.
Fundamentals
A balanced chemical equation is the one which has equal number of atoms of elements on the reactant’s side as well as the product’s side of the equation. When an equation is balanced, it then obeys the law of conservation of mass. There are different types of methods to balance a chemical equation like inspection, algebraic, and oxidation number method.
Answer:
A
The equation to be balanced is given as follows:
Cr (chromium) gains 3 electrons and changes from +6 to +3 oxidation state. Therefore, it is getting reduced and acts as an oxidising agent.
S (sulphur) loses 2 electrons and changes from +4 to +6 oxidation state. Therefore, it is getting oxidised and acts as a reducing agent.
To balance the electrons. Multiply the compounds containing chromium by 2 and the compounds containing sulphur by 3. This gives the following equation:
The next step is to balance the oxygen and hydrogen on both the sides. This gives the following equation:
Finally, balance the remaining atoms (chlorine and potassium) and the whole equation will be balanced. This gives the following equation:
The coefficients for each compound in the order in which they appear in the equation are
2,3,10,4,3,2,5.
B
