reaction products are insoluble in water. Examples of substances that are not soluble in
in water, which is CaCO3 and BaCO3.
To determine the solubility of a substance required knowledge
as a result of empirical measurement of various substances.
Consider the reaction between calcium chloride and sodium phosphate follows.
3CaCl2 + 2Na3PO4 - → Ca3 (PO4) 2 + 6NaCl
NaCl will dissolve in water, while Ca3 (PO4) 2 are insoluble.
Phosphate compounds most soluble in water, except for compounds
phosphate of sodium, potassium, and ammonium. Therefore, equation
reaction can be written as follows.
3CaCl2 (aq) + 2Na3PO4 (aq) - → Ca3 (PO4) 2 (s) + 6NaCl (aq)
By removing the ion-ion reaction spektator in equation
that, perasamaan net ion of the reaction can be obtained.
3Ca2 + (aq) + 2PO4
3 - (aq) - → Ca3 (PO4) 2 (s)
Predicting Reaction Formation
Write the molecular equation and net ionic equation of the following reactions.
Al2 (SO4) 3 + 6NaOH - → 2Al (OH) 3 + 3Na2SO4
Answer:
According to the empirical data known to soluble aluminum sulfate, whereas aluminum
insoluble hydroxide. Therefore, the precipitation reaction will occur.
Al2 (SO4) 3 (aq) + 6NaOH (aq) - → 2Al (OH) 3 (s) + 3Na2SO4 (aq)
To obtain the net ionic equation, list the substances that are dissolved as ions and
spektator ions are ignored.
2Al3 + (a) + 3SO4
2 - (aq) + 6Na + (aq) + 6OH-(aq) → 2Al (OH) 3 (s) + 6Na + (aq) +
3SO4
2 - (aq)
Thus, the following net ionic equation.
Al3 + (aq) + 3OH-(aq) - → Al (OH) 3 (s)














