Question

using the letters a,b,c and d create a model of a double replacement reaction
ac + bd --> ab + c + d
ab + cd --> ac + bd
ab + cd --> a + bc + d
ac + bd --> ad + bc

Explanation:

Step1: Recall double - replacement reaction definition

In a double - replacement reaction, the general form is \(AB + CD\to AD+BC\). The cations and anions of the two reactant compounds exchange partners.

Step2: Analyze each option

• Option 1: \(AC + BD\to AB + C + D\) does not follow the double - replacement pattern of ion exchange between two compounds.
• Option 2: \(AB + CD\to AC + BD\) is not the correct double - replacement pattern.
• Option 3: \(AB + CD\to A + BC + D\) is not a double - replacement reaction (it looks more like a decomposition or single - replacement in a wrong form).
• Option 4: \(AC + BD\to AD + BC\) follows the \(AB + CD\to AD + BC\) pattern where \(A\) and \(B\) (from \(AC\) and \(BD\)) exchange partners.

Answer:

\(AC + BD\to AD + BC\)