When quicklime or calcium oxide (CaO) reacts with water, slaked lime [Ca(OH)2] is formed. During this reaction, a large amount of heat is released. So, this reaction is an exothermic Reaction.
. 𝐶𝑎𝑂(𝑠) + 𝐻2𝑂(𝑙) → 𝐶𝑎(𝑂𝐻)2(𝑎𝑞) + ℎ𝑒𝑎𝑡
𝑐𝑎𝑙𝑐𝑖𝑐𝑖𝑢𝑚 𝑜𝑥𝑖𝑑𝑒 (𝑞𝑢𝑖𝑐𝑘 𝑙𝑖𝑚𝑒) 𝑤𝑎𝑡er (𝑐𝑎𝑙𝑐𝑖𝑢𝑚 ℎ𝑦𝑑𝑟𝑜𝑥𝑖𝑑𝑒(𝑠𝑙𝑎𝑘𝑒𝑑 𝑙𝑖𝑚𝑒)