Question

Arrange the following elements in increasing order of metallic character
Si, Be, Mg, Na, P

Answer 1

Metallic character increases down a group and decreases along a period as we move from left to right. The vertical columns on the periodic table are called groups because of their similar chemical behavior. All the members of a group of elements have the same number of valence electrons and similar chemical properties. The horizontal rows on the periodic table are called periods.

Complete Step By Step Solution
Metallic character increases down a group as we can see from the periodic table Na is present in group-1, Be and Mg are present in group-2. So, down the group the metallic character of Mg will be more than Be. And Mg, Na, Si and P are present in the same period-3. As we know metallic character decreases along a group so in period-3, Na will have the highest metallic character then Mg, then Si and then P.
So, we get the series in decreasing order as: $Na>Mg>Be>Si>P$ .

Additional Information
Metallic character refers to the level of reactivity of a metal. Metals tend to lose electrons in chemical reactions, as indicated by their low ionization energies. Metallic character increases as you move down the periodic table. This is due to the fact that the electrons become easier to lose as the atomic radius increases. The increase in atomic radius decreases attraction between the positive nucleus and the negative electrons, causing the electrons to be held more loosely. Metals are lustrous, malleable, ductile, good conductors of heat and electricity. The elements which have a tendency to gain electrons are known as non-metals. The tendency to gain electrons increases on moving across a period due to an increase in the nuclear charge and decrease in the atomic size. Hence, the non-metallic character increases across a period.

Note
Study the periodic table properly. One should clearly understand the difference between groups and periods. Metals have the tendency to lose electrons depicting their metallic character and non-metals have the tendency to gain electrons. Metals are solids at room temperature with the exception of mercury, which is liquid at room temperature.