Meyer was just four years older than Mendeleev, and produced several Periodic Tables between 1864-1870. His first table contained just 28 elements, organised by their valency (how many other atoms ...

Now in the Periodic Table the valency for oxygen, an electro-negative element, increases regularly as we pass from Group 0 to Group VIII, while that for hydrogen, an electro-positive element ...

In this study guide, you can revise how the periodic table arranges elements according ... The formula can be worked out using the valency. Balanced equations Chemical equations must be balanced ...