$\Al ( NO _3)_3(aq)$ and $Na _3 PO _4(aq)$
$\xrightarrow[\text { Molecular Equation }]{ Al _{\left( NO _3\right)_3( aq )}+ AlPO _4 \quad Na }$
Complete Ionic Equation
Net Ionic Equation
Spectator Ions
Answer (1)
The balanced molecular equation is A l ( N O 3 ) 3 ( a q ) + N a 3 P O 4 ( a q ) → A lP O 4 ( s ) + 3 N a N O 3 ( a q ) .
The complete ionic equation is A l 3 + ( a q ) + 3 N O 3 − ( a q ) + 3 N a + ( a q ) + P O 4 3 − ( a q ) → A lP O 4 ( s ) + 3 N a + ( a q ) + 3 N O 3 − ( a q ) .
The net ionic equation is A l 3 + ( a q ) + P O 4 3 − ( a q ) → A lP O 4 ( s ) .
The spectator ions are N a + and N O 3 − .
Explanation
Problem Analysis We are given the reactants Aluminum Nitrate ( A l ( N O 3 ) 3 ( a q ) ) and Sodium Phosphate ( N a 3 P O 4 ( a q ) ). Our goal is to determine the balanced molecular equation, complete ionic equation, net ionic equation, and spectator ions for the reaction.
Balanced Molecular Equation First, we write the balanced molecular equation. Aluminum Nitrate reacts with Sodium Phosphate to form Aluminum Phosphate ( A lP O 4 ) which is a solid precipitate, and Sodium Nitrate ( N a N O 3 ) which is soluble in water. The balanced molecular equation is: A l ( N O 3 ) 3 ( a q ) + N a 3 P O 4 ( a q ) → A lP O 4 ( s ) + 3 N a N O 3 ( a q )
Complete Ionic Equation Next, we write the complete ionic equation by dissociating all aqueous species into their ions: A l 3 + ( a q ) + 3 N O 3 − ( a q ) + 3 N a + ( a q ) + P O 4 3 − ( a q ) → A lP O 4 ( s ) + 3 N a + ( a q ) + 3 N O 3 − ( a q )
Spectator Ions Now, we identify the spectator ions, which are the ions that appear on both sides of the complete ionic equation. In this case, the spectator ions are Sodium ( N a + ) and Nitrate ( N O 3 − ).
Net Ionic Equation Finally, we write the net ionic equation by removing the spectator ions from the complete ionic equation: A l 3 + ( a q ) + P O 4 3 − ( a q ) → A lP O 4 ( s )
Final Answer Therefore, the balanced molecular equation is: A l ( N O 3 ) 3 ( a q ) + N a 3 P O 4 ( a q ) → A lP O 4 ( s ) + 3 N a N O 3 ( a q ) The complete ionic equation is: A l 3 + ( a q ) + 3 N O 3 − ( a q ) + 3 N a + ( a q ) + P O 4 3 − ( a q ) → A lP O 4 ( s ) + 3 N a + ( a q ) + 3 N O 3 − ( a q ) The net ionic equation is: A l 3 + ( a q ) + P O 4 3 − ( a q ) → A lP O 4 ( s ) The spectator ions are N a + and N O 3 − .
Examples
This type of reaction is important in water treatment. For example, aluminum sulfate ( A l 2 ( S O 4 ) 3 ) is used to remove phosphate from wastewater by forming a precipitate of aluminum phosphate. This helps to prevent eutrophication in lakes and rivers, which is caused by excessive levels of nutrients like phosphate.
