I believe Mendeleev formed his periodic table by atomic weight (nowadays we do it by atomic number) so he likely used those values.
1. Two parallel normal faults form.
4. The hanging wall on the left slides down relative to the footwall.
5. The hanging wall on the right slides down relative to the footwall.
This is a law because it describes the force but makes not attempt to explain how the force works. A theory is an explanation of a natural phenomenon. Einstein's General Theory of Relativity explains how gravity works by describing gravity as the effect of curvature of four dimensional spacetime.
<span>
some elements have their outer electrons more tightly bound than
others. Those who have less tightly bound electrons are more reactive.
After this it gets more complex in explaining why they are bound with
different strengths. </span>
