Question

how many valence electrons does each atom of arsenic (as) have? arsenic is element 33. it is in period 4 and family 15 (5a or the nitrogen family) (1 point)
15
5
4
33

Explanation:

Step1: Recall valence electron rule for groups

For main - group elements (groups 1, 2, 13 - 18), the number of valence electrons is equal to the group number (for groups 1 and 2) or the group number minus 10 (for groups 13 - 18).

Step2: Determine the group of Arsenic

Arsenic (As) is in group 15 (5A). Since group 15 is a main - group (representative) group and the group number is between 13 - 18, we use the rule: number of valence electrons = group number - 10.
For group 15, valence electrons = 15 - 10 = 5. Also, elements in the nitrogen family (group 15) like N, P, As, etc., have 5 valence electrons. The options 15 (group number, not valence electrons), 4 (incorrect), and 33 (atomic number, not valence electrons) can be eliminated.

Answer:

5 (corresponding to the option with "5")