Question

which of the following is the correct net ionic equation for the reaction that occurs when aqueous solutions of sodium phosphate and calcium perchlorate are mixed?
a. $3ca^{2 + }(aq) + 2po_{4}^{3 - }(aq)→ca_{3}(po_{4})_{2}(s)$
b. $ca^{2 + }(aq) + 2clo_{4}^{-}(aq)→ca(clo_{4})_{2}(s)$
c. $na^{ + }(aq) + clo_{4}^{-}(aq)→naclo_{4}(s)$
d. $3na^{ + }(aq) + po_{4}^{3 - }(aq) + ca^{2 + }(aq)→na_{3}po_{4}(s) + ca^{2 + }(aq)$
e. $napo_{4}(aq) + caclo_{4}(aq)→capo_{4}(s) + naclo_{4}(aq)$
f. $na_{3}po_{4}(aq) + ca(clo_{4})_{2}(aq)→no reaction$

Explanation:

Step1: Write the chemical formulas

Sodium phosphate is \(Na_3PO_4\) (dissociates into \(3Na^{+}(aq)+PO_{4}^{3 -}(aq)\) in aqueous solution), calcium perchlorate is \(Ca(ClO_4)_2\) (dissociates into \(Ca^{2+}(aq)+2ClO_{4}^{-}(aq)\) in aqueous solution).

Step2: Predict the products of the double - displacement reaction

By double - displacement (where cations and anions exchange partners), the possible products are \(NaClO_4\) and \(Ca_3(PO_4)_2\). According to solubility rules, \(NaClO_4\) is soluble (all perchlorates are soluble, and sodium salts are soluble), and \(Ca_3(PO_4)_2\) is insoluble.

Step3: Write the complete ionic equation

\(3Na^{+}(aq)+PO_{4}^{3 -}(aq)+Ca^{2+}(aq)+2ClO_{4}^{-}(aq)\to3Na^{+}(aq)+2ClO_{4}^{-}(aq)+Ca_3(PO_4)_2(s)\)

Step4: Cancel out the spectator ions (\(Na^{+}\) and \(ClO_{4}^{-}\))

The net ionic equation is \(3Ca^{2+}(aq)+2PO_{4}^{3 -}(aq)\to Ca_3(PO_4)_2(s)\)

Answer:

A. \(3Ca^{2 +}(aq)+2PO_{4}^{3 -}(aq)\to Ca_{3}(PO_{4})_{2}(s)\)