matter can be created and destroyed matter can be created and destroyed proportions of various atoms discovered by Antoine Lavoisier in 1789 matter can be created and destroyed matter can be created and destroyed matter can be created and destroyed proportions of various atoms matter can be created and destroyed matter can be created and destroyed matter can be created and destroyed «The Conservation of Mass | Learn Science at Scitable» matter can be created and destroyed matter can be created and destroyed matter can be created and destroyed matter can be created and destroyed matter can be created and destroyed proportions of various atoms matter can be created and destroyed The Conservation of Mass | Learn Science at Scitable «The Conservation of Mass | Learn Science at Scitable» matter can be created and destroyed matter can be created and destroyed proportions of various atoms matter can be created and destroyed «The Conservation of Mass | Learn Science at Scitable» matter can be created and destroyed matter can be created and destroyed matter can be created and destroyed proportions of various atoms matter can be created and destroyed "The conservation of mass" matter can be created and destroyed conservation of mass