Answer:
The answer will be ：
In year 1869
Russian scientist named Dmitri Mendeleev
Chart called Mendeeleves periodic table
increasing atomic masses
physical and chemical properties.
Hope this Helps
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Answer:
1.
Explanation:
1. They are made up of two or more Pure substances that are not chemically bonded together and appear non-uniform
A heterogeneous mixture is not chemically combined and its components are visible and can be seen.
amount of product formed or amount of reactants used / time
I believe the answer would be c?? I’m not too sure though
