Chemistry in ancient poetry: (1) Ancient poetry is the precious spiritual wealth left by the ancients for us. Which of the following poems only involves physical changes is ______. A.

(1) A. New substances are generated during the burning process of wildfire, which is a chemical change.

B. As long as you work hard enough, the process of grinding the iron pestle into a needle will only change the state, and no new matter will be generated. It is a physical change.

C. New substances are generated during the process of the wax torch becoming ashes, which is a chemical change.

D. New substances are generated during the sound of firecrackers, which is a chemical change.

So choose: B.

(2) To dig out the mountains with thousands of hammers is to mine limestone. No new material is generated during the process, which is a physical change.

If the fire burns easily: Calcium carbonate decomposes at high temperature to generate calcium oxide and carbon dioxide. The chemical equation of the reaction is: CaCO3?High temperature?.?CaO+CO2↑;

You are not afraid of being broken into pieces: Calcium oxide reacts with water to form calcium hydroxide. The chemical equation of the reaction is: CaO+H2O═Ca(OH)2;

To stay innocent in the world: Calcium hydroxide reacts with carbon dioxide in the air to form carbonic acid The chemical equation of the reaction between calcium precipitation and water is: Ca(OH)2+CO2═CaCO3↓+H2O.

So the answer is: CaCO3?High temperature?.?CaO+CO2↑; CaO+H2O═Ca(OH)2; Ca(OH)2+CO2═CaCO3↓+H2O．

(3) Since molecules are constantly moving, floral molecules enter people’s noses through movement and touch olfactory cells, so they smell the fragrance.

So the answer is: molecules are constantly moving. Through movement, floral molecules enter people's noses and touch olfactory cells, so they smell the fragrance.