Question

all the elements of a family in the periodic table have what feature in common? a they all have similar chemical properties. b they all have the same number of protons in the nucleus. c they are all located in the same horizontal row or period. d they all have the same number of electrons in the electron cloud.

Explanation:

• Option A: Elements in a family (group) of the periodic table have the same number of valence electrons, which leads to similar chemical properties. This is a key characteristic of groups.
• Option B: The number of protons is the atomic number, and each element has a unique atomic number, so elements in a family do not have the same number of protons.
• Option C: Elements in the same horizontal row (period) have the same number of electron shells, not the same family feature. Families are vertical columns.
• Option D: Elements in a family have the same number of valence electrons, not the total number of electrons in the electron cloud (which increases down a group as more electron shells are added).

Answer:

A. They all have similar chemical properties.