Question

All chemical reactions have a conservation of(1) mass, only(2) mass and charge, only(3) charge and energy, only(4) mass, charge, and energy

Answer 1

Answer: The correct answer is option 4.

Explanation:

Law of conservation of mass states that mass can neither be created nor be destroyed, but it can only be transformed from one form to another. It always remain conserved. In a chemical reaction, mass on the reactant side will be equal to the mass on the product side.

For Example: Reaction of hydrogen and oxygen to form water.

$2H_2+O_2\rightarrow 2H_2O$

Mass on the reactant side: $[tex][2(2\times 1)+(2\times 16)]=36g/mol$

Mass on the product side: $[2\times ((2\times 1)+16)]=36g/mol$

Law of conservation of energy states that energy can neither be created not be destroyed, but it can only be transformed from one form to another. In a chemical reaction, energy given to the reactants is released in the forma of energy of the products.

For Example: Melting of ice. In this process, the energy given to the ice is released in the form of kinetic energy of the water molecules (product).

Law of Conservation of charge states that charge can neither be created not be destroyed, but it can only be transformed from one form to another. In a chemical reaction, total charge on the reactant side will always be equal to the total charge on the product side.

For Example: Reduction of chlorine gas. The chemical equation follows:

$Cl_2+2e^-\rightarrow 2Cl^-$

Total charge on the reactant side = -2

Total charge on the product side = -2

From the above information, the correct answer is Option 4.