How many valence electrons do alkaline earth metals have

Explanation:

Alkaline earth metals are the family of metals that belong to group (column) number 2 in the periodic table.

You can tell the number of valence electrons of the representative elements by the number of column: the ones digit is the number of valence electrons.

This is how this works:

Column number   ones digit     number of valence electrons

1                                  1                  1 (alkali metals)

2                                 2                 2 (alkaline earth metals)

13                                3                 3

14                                4                 4

15                                5                 5

16                                6                 6

17                                 7                 7 (halogens)

18                                 8                 8 (noble gases).

Of course, this is consequence of the electron configurations.

the answer is 303.15 or 303