Balancing Ionic Equations and Solubility

This video tutorial explains how to balance the net ionic equation for phosphoric acid and magnesium hydroxide. It begins with balancing the molecular equation, followed by determining the states of the compounds using solubility rules. The video then demonstrates how to write the complete ionic equation and identify the net ionic equation by eliminating spectator ions. Key points include recognizing phosphoric acid as a weak acid and understanding solubility rules for hydroxides and phosphates.

What is the first step in balancing a net ionic equation?

• Identify spectator ions

• Balance the molecular equation

• Write the complete ionic equation

• Determine the solubility of compounds

How many phosphates are needed to balance the molecular equation?

• One

• Three

• Four

• Two

What state is phosphoric acid in when dissolved in water?

• Solid

• Liquid

• Gas

• Aqueous

Why is magnesium hydroxide considered insoluble?

• It reacts violently with water

• It forms a gas in water

• It does not dissolve much in water

• It dissolves completely in water

What is the state of magnesium phosphate in the reaction?

• Aqueous

• Solid

• Liquid

• Gas

What is the purpose of writing a complete ionic equation?

• To identify spectator ions

• To balance the equation

• To determine solubility

• To find the net ionic equation

Why are weak acids not split into ions in the ionic equation?

• They are highly reactive

• They are gases

• They do not dissociate much

• They are solids

What is the net ionic equation for the reaction between phosphoric acid and magnesium hydroxide?

• H3PO4 + Mg(OH)2 → Mg2+ + PO4^3- + H2O

• 2 H3PO4 + 3 Mg(OH)2 → 3 Mg2+ + 2 PO4^3- + 6 H2O

• 2 H3PO4 + 3 Mg(OH)2 → Mg3(PO4)2 + 6 H2O

• H3PO4 + MgOH2 → Mg3(PO4)2 + H2O

What is the key to writing the net ionic equation for this reaction?

• Understanding solubility rules

• Identifying spectator ions

• Recognizing weak acids

• Balancing the molecular equation

What is the state of water in the net ionic equation?

• Solid

• Liquid

• Aqueous

• Gas