A) most reactions involve bond breaking and bond making. this equation shows what happens when methane (ch4) burns in oxygen (o2). mark the bonds broken in blue and the bonds formed in red.\

When CH₄ burns with the presence of O₂, CO₂ and H₂O are formed as the products. The balanced equation is;

CH₄ + 2O₂ → CO₂ + 2H₂O

When the reaction happens, 4 C-H bonds of CH₄ and O=O bond of O₂ are broken down to form 2 C=O bonds in CO₂ and 2 O-H bonds in H₂O.

The broken and formed bonds are marked in the image.

The unbalanced chemical equation is-

Li2O + H2O → LiOH

In order to balance the equation # atoms of a particular type on the reactants must be equal to the # atoms of the same type on the products

Reactants               Products

Li = 2                       Li = 1

O = 2                       O = 1

H = 2                        H = 1

The balanced equation is -

(1)Li2O + (1)H2O → (2)LiOH