Here's how to write the molecular equation for the reaction between cobalt(II) nitrate and potassium phosphate:

1. Identify the reactants and products:

* Reactants: Cobalt(II) nitrate (Co(NO₃)₂) and potassium phosphate (K₃PO₄)

* Products: Cobalt(II) phosphate (Co₃(PO₄)₂) - a precipitate

and potassium nitrate (KNO₃) - soluble

2. Write the unbalanced equation:

Co(NO₃)₂(aq) + K₃PO₄(aq) → Co₃(PO₄)₂(s) + KNO₃(aq)

3. Balance the equation:

To balance the equation, we need to adjust the coefficients in front of each compound:

3Co(NO₃)₂(aq) + 2K₃PO₄(aq) → Co₃(PO₄)₂(s) + 6KNO₃(aq)

The balanced molecular equation is:

3Co(NO₃)₂(aq) + 2K₃PO₄(aq) → Co₃(PO₄)₂(s) + 6KNO₃(aq)