مصادر الكيمياء موقع لتعليم الكيمياء بصورة مبسطة
The law of Conservation of Mass states that the mass of matter before and after a chemical change remains the same. The number of atoms also remains the same. The only thing that changes is the arrangement of the atoms. For example, the mass of hydrogen and oxygen before they …
أكمل القراءة »