Help me please 1) information about the atomic structure (structure of the atom)

2) information about the periodic table of the elements and the classification of the elements​

What does x represent in the formula for the compound xcl4?

Give the set of reactants (including an alkyl halide and a nucleophile) that could be used to synthesize the following ether: draw the molecules on the canvas by choosing buttons from the tools (for bonds and charges), atoms, and templates toolbars, including charges where needed. ch3ch2och2ch2chch3 | ch3

Explain in detail of the four major scientific developments that spurred the formulation of the plate tectonics theory