Question

1. choose the best answer.

elements in a group have similar properties due to ______
atomic number
valence electrons
protons
neutrons

1. choose the best answer.

how do you determine the number of valence electrons an element has?
it is the same number as the last digit of the group number.
it is the same as the atomic mass.
it is the same number as the period number.
it is the same as the atomic number.

Explanation:

1. Elements in the same group of the periodic table have identical numbers of valence electrons, which dictates their chemical behavior and properties.
2. For main group elements, the number of valence electrons matches the last digit of the group number (e.g., Group 13 elements have 3 valence electrons).

Answer:

1. valence electrons
2. It is the same number as the last digit of the group number.