Question

which of the following is the correct
dissociation reaction for calcium hydroxide?

ca(oh)2(s) -------> ca2+(aq) + 2oh−(aq)

caoh(s) -----> ca+(aq) + oh−(aq)

ca(oh)2(s) -------> 2ca2+(aq) + oh−(aq)

ca(oh)2(s) ---------> 2 ca2+(aq) + 2oh−(aq

hydrogen chloride gas dissolves in water as
follows: hcl(g) -----> h+(aq) + cl−(aq)
this reaction is classified as

dissociation

separation

ionization

none of them

according to its arrhenius definition, a weak
base

fully reacts with water to form oh−(aq)

partially reacts with water to form oh−(aq)

completely dissociates to form oh−(aq)

has very high ph

Explanation:

1. For calcium hydroxide dissociation: Calcium hydroxide has the formula $\text{Ca(OH)}_2$. It dissociates into one $\text{Ca}^{2+}$ ion and two $\text{OH}^-$ ions when dissolved in water, balancing charge and stoichiometry.
2. For HCl reaction classification: Ionization is the process where a neutral molecule forms ions in solution. HCl is a neutral gas that forms $\text{H}^+$ and $\text{Cl}^-$ in water, which fits ionization (dissociation applies to ionic compounds breaking apart, not neutral molecules forming ions).
3. For weak base definition (Arrhenius): An Arrhenius weak base does not fully react with water; only a portion of the base molecules produce $\text{OH}^-$ ions in solution, unlike strong bases that fully dissociate/react.

Answer:

1. $\text{Ca(OH)}2(\text{s})

ightarrow \text{Ca}2+(\text{aq}) + 2\text{OH}-(\text{aq})$

1. ionization
2. partially reacts with water to form $\text{OH}-(\text{aq})$