When aqueous solutions of sodium cyanide and hydrobromic acid are mixed, an aqueous solution of sodium bromide and hydrocyanic acid results. Write the net ionic equation for the reaction.

CN⁻(aq) + H⁺(aq) → HCN(l)

Explanation:

The reactants are aqueous solutions:

NaCN(aq) and HBr(aq)

When you mix these compounds you make pure HCN (l)

The molecular equation is:

NaCN(aq) + HBr(aq) → NaBr(aq) + HCN(l)

When you dissociate the reactants, you have:

Na⁺(aq) +CN⁻(aq) + H⁺(aq) + Br⁻(aq) → Na⁺(aq) + Br⁻(aq) + HCN(l)

Sodium bromide, it is a salt, that can also be dissociated in the solution

To make, the net ionic equation you remove the repeated ions

CN⁻(aq) + H⁺(aq) → HCN(l)

The oxygen atom holds the electrons in a covalent bond more closely than the hydrogen atoms and develops a partial negative charge.

Explanation:

Water molecule is composed two hydrogen atoms and one oxygen atom.Both the hydrogen atom interact with the single oxygen by the formation of covalent bond.

  Although the covalent bond is formed but the bonding electrons are not shared equally by both the atom.As oxygen is more electronegative than that of hydrogen atom,oxygen attract the bonding electron pair towards itself.

  As a result the hydrogen atom get partial positive charge and oxygen atom gains partial negative charge.