Question

Which of the following is a double replacement reaction?

a. CuO + H₂ → Cu + H₂O

b. HBr + KOH → H₂O + KBr

c. SO₂ + H₂O → H₂SO₃

d. 2HI → I₂ + H₂

Answer 1

Option b, HBr + KOH → H₂O + KBr, is the double replacement reaction because it involves the exchange of ions between two compounds, resulting in the formation of water and potassium bromide.

Step-by-step explanation:

The question is asking which of the provided reactions is a double replacement reaction. A double replacement reaction is one where two compounds exchange ions with each other, resulting in the formation of two new compounds. In option b, HBr + KOH → H₂O + KBr, we can see that the hydrogen ion (H+) from HBr exchanges places with the potassium ion (K+) from KOH, resulting in the formation of water (H₂O) and potassium bromide (KBr), which fits the criteria for a double replacement reaction.

Answer 2

HBr + KOH → H₂O + KBr, is the double replacement reaction where an acid and a base react to form water and a salt. The correct option is b.

Step-by-step explanation:

The double replacement reaction in the options provided is b. HBr + KOH → H₂O + KBr. This is a type of chemical reaction where the anions and cations of two different molecules switch places, forming two entirely new compounds. In this case, hydrogen bromide (HBr), a strong acid, reacts with potassium hydroxide (KOH), a strong base, to form water (H₂O) and potassium bromide (KBr), demonstrating the typical acid-base reaction that results in a salt and water.

Hence, b is the correct option.