8 elements
There are 8 elements in the third period of periodic table. The elements belong to group-1,2,13,14,15,16,17 and 18
Eight. Sodium, Magnesium, Aluminium, Silicon, Phosphorous, Sulfur, Chlorine, Argon
There are eight third period transition elements on the periodic table.
There are 2 elements in the first period, 8, 8 elements in 2nd and 3rd periods respectively,
8 - Na, Mg, Al, Si, P, S, Cl, Ar
NA and MG are bridge elements because some of the second period elements show a diagonal relationship with the third period elements. Other examples would be LI and MG.
Period 1: 2 elements Period 2: 8 elements Period 3: 8 elements Period 4: 18 elements Period 5: 18 elements Period 6: 32 elements Period 7: 25 elements
103
There are 18 elements in period 4.
there are 32 elements in period 6.
18
Now (January 2012) the periodic table of Mendeleev contain 118 chemical elements.