Identify the -ing form as the Participle or the Gerund. Hydrogen chloride is usually prepared by heating a mixture of concentrated sulphuric acid and the appropriate salt. Вопрос 17 Ответ a. gerund b. participle I

In the sentence "heating a mixture of concentrated sulphuric acid and the appropriate salt," the word "heating" is functioning as a participle. A participle is a verbal that functions as an adjective, modifying a noun or pronoun in a sentence. It is derived from a verb, but functions as an adjective.