Réponse :
Tiens recopie ce schéma d'une transformation chimique .
https://www.google.com/url?sa=i&url=https%3A%2F%2Fslideplayer.fr%2Fslide%2F472255%2F&psig=AOvVaw1TNO9-qowNu6qc9MAxQYe6&ust=1648028460325000&source=images&cd=vfe&ved=0CAsQjRxqFwoTCKDEo8y22fYCFQAAAAAdAAAAABAJ
Explications :