Explain which of the five types of reactions this is, and justify your answer.
[tex]AlBr _3+ K _2 SO _4= KBr + Al _2( SO _4)_3[/tex]
Answer (1)
Balance the chemical equation: 2 A lB r 3 + 3 K 2 S O 4 → 6 K B r + A l 2 ( S O 4 ) 3 .
Identify the reactants and products: Reactants are A lB r 3 and K 2 S O 4 , products are K B r and A l 2 ( S O 4 ) 3 .
Determine the reaction type: The cations of the two compounds switch places.
Conclude that this is a double replacement reaction: d o u b l e re pl a ce m e n t
Explanation
Understanding the Reaction We are given the chemical reaction: A lB r 3 + K 2 S O 4 = K B r + A l 2 ( S O 4 ) 3 We need to identify which of the five types of reactions this is and provide a justification. The five types of reactions are synthesis, decomposition, single replacement, double replacement, and combustion.
Balancing the Equation First, let's balance the chemical equation. To balance the equation, we need to make sure that the number of atoms of each element is the same on both sides of the equation. The balanced equation is: 2 A lB r 3 + 3 K 2 S O 4 → 6 K B r + A l 2 ( S O 4 ) 3 Now we have 2 Al atoms, 6 Br atoms, 6 K atoms, and 3 S O 4 groups on both sides of the equation.
Identifying Reactants and Products Next, let's identify the reactants and products. The reactants are A lB r 3 and K 2 S O 4 , and the products are K B r and A l 2 ( S O 4 ) 3 .
Determining the Reaction Type Now, let's determine the type of reaction. In this reaction, two compounds ( A lB r 3 and K 2 S O 4 ) react, and the cations of the two compounds switch places. Specifically, Al switches places with K. This is the definition of a double replacement reaction.
Justifying the Answer Therefore, the reaction is a double replacement reaction because the cations of the two reacting compounds switch places.
Examples
Double replacement reactions are commonly used in various applications, such as water softening and precipitation reactions. For example, in water softening, calcium or magnesium ions are removed from hard water by adding a chemical that causes them to precipitate out of solution as a solid. This process involves the exchange of ions between the added chemical and the calcium or magnesium ions in the water, which is a double replacement reaction. Another example is the reaction between silver nitrate and sodium chloride to form silver chloride precipitate, which is used in photography.
