Question

the number of valence electrons in group 13 is ______.
○ 13
○ 3
○ 5
○ the same as it’s penod number

Explanation:

In the periodic table, for main - group elements (Groups 1 - 2 and 13 - 18), the number of valence electrons is equal to the group number (for Groups 13 - 18, we subtract 10 from the group number). For Group 13, the number of valence electrons is \(13 - 10=3\). The option "13" is incorrect as it confuses group number with valence electrons. The option "5" is wrong as it doesn't follow the valence electron - group number relationship for Group 13. The option "the same as its period number" is incorrect because the period number relates to the number of electron shells, not valence electrons.

Answer:

B. 3 (assuming the options are labeled as A. 13, B. 3, C. 5, D. the same as it’s period number)