Answer:
substitution is the best method or collecting like terms
Explanation:
Answer is: (2) Chemical energy is converted to electrical energy.
An electrochemical cell (voltaic or galvanic cell) is generating electrical energy from chemical reactions.
In galvanic cell, specie (for example zinc and zinc cations) from one half-cell, lose electrons (oxidation) and species from the other half-cell (for example copper and copper cations) gain electrons (reduction).
Oxidation on the zinc anode: Zn(s) → Zn²⁺(aq) + 2e⁻.
Reduction on the copper cathode: Cu²⁺(aq) + 2e⁻ → Cu(s).
Explanation:
An equation is said to be balanced when the number of atoms on both reactant and product side are equal in number.
Whereas an equation where electrolytes in an aqueous solution are represented as dissociated ions is known as an ionic equation.
For example,
can be represented in ionic form as follows.

Now, cancelling the common ions present on both sides of the equation. The resulting, ionic equation will be as follows.
