The elements in groups 1A through 8A (also known as the main group elements) have the following in common:
a. They all have similar properties - This is correct. Elements within the same group often exhibit similar chemical and physical properties.
d. They all have the same number of valence electrons - This is also correct. Each group (column) in the periodic table corresponds to elements that have the same number of valence electrons.
e. They all will have the same oxidation states for the ions they form - This is partially correct. While many elements in a group have similar oxidation states, not all elements will strictly follow this for all compounds. However, typical oxidation states can often be predicted based on group number.
The other options are not correct:
b. They were all discovered around the same time - This is incorrect. The discovery of elements occurred over a wide range of time periods, not all around the same time.
c. They all have the same number of energy shells - This is incorrect. Different periods (rows) have different numbers of energy shells. For example, elements in the 1st period have 1 energy shell, while those in the 4th period have 4 energy shells.
So, the correct answers are a, d, and e (with the caveat regarding oxidation states).
1 answer