Question

Second period of periodic table has how many metals?

Answer 1

Hint: It corresponds to the filling of electrons in the second energy shell in L shell. Since this energy shell has only four orbital \[{\text{(2s and 2p)}}\] that means it can accommodate only eight electrons, therefore the second periods contain only eight elements.

Complete answer:
Only Lithium and beryllium are metals.
It starts with Li which has atomic number \[{\text{3}}\] and has three electrons, where two electrons are in \[{\text{1s}}\] orbital and third electron enters the \[{\text{2s}}\] orbital. The next element is beryllium, the atomic number is \[{\text{4}}\], which means it has four electrons. Where two electrons are in the 1s orbital and the next two electrons in2s orbital.
Those elements are classified into \[s,p,d{\text{ and f}}\] block, it is possible to further classify them into metals, nonmetals and metalloids. More than \[78\% \] of the known elements are metals. These elements are present on the left side and centre of the periodic table. Metals are the elements which are malleable and ductile, possess lustre, are good conductors of heat and electricity and have high densities. Metals usually have high melting point, and high boiling points and generally are solid at room temperature.

Note:
Non-metals are much lesser than metals in a periodic table. There are about twenty non- metals. These are placed on the top right-hand side of the periodic table. They usually are solid or gases at room temperature. They are neither ductile nor malleable. They have poor conductance of heat and electricity. Non-metallic character increases from left to right.