A Halogen.
lithium
perodic law
according to their increasing atomic numbers.
There are 18 groups and 7 periods in the modern periodic table.
Search: Groups on Periodic Table on google.
All chemical elements are placed in the perodic table of elements of Mendeleev.
If you are talking about groups or families, the left side consists of all metals
At last count we were up to 114.
A Halogen.
I think it was Mendaleev's periodic table.
meercury , lead
Copper
lithium
Phosphorus
check out an interesting periodic table at www.calculatoredge.com
lanthanum is a element on the perodic table ...