Periodic Table
Which elements are malleable?
Metals
Where are metalloids located?
Along the staircase
Which elements are usually semiconductors?
Metalloids
Why is Hydrogen in Group 1 with the metals?
It is a gas with an atomic number of 1, it is also unstable like the Alkali metals.
What does the term 'valence electrons' mean?
number of electrons on outermost shell
Who organized the modern Periodic Table?
Dimitri Mendeleev