Explain the law of conservation of mass in terms of the atoms and bonds in a chemical reaction.

no matter is destroyed or created, it merely changes form. In terms of atoms and bonds, there will be the same amount of atoms at the beginning of an experiment as the amount of atoms at the end of experiment. All that will have happened, is that during the reaction, bonds will have been broken and formed making new compounds. However, the amount of atoms remains exactly the same because matter can not be created or destroyed

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