Question

Arrange the following groups of atoms in order of increasing size. a. \(\mathrm{Rb}, \mathrm{Na}, \mathrm{Be}\) b. \(\mathrm{Sr}, \mathrm{Se}, \mathrm{Ne}\) c. \(\mathrm{Fe}, \mathrm{P}, \mathrm{O}\)

Short answer

The order of increasing size for the given groups of atoms is: a. \(\mathrm{Be} < \mathrm{Na} < \mathrm{Rb}\) b. \(\mathrm{Ne} < \mathrm{Se} < \mathrm{Sr}\) c. \(\mathrm{O} < \mathrm{P} < \mathrm{Fe}\)

Step-by-step solution

Determine the position of elements in the periodic table

Rb is in Group 1 and Period 5, Na is in Group 1 and Period 3, and Be is in Group 2 and Period 2.

Compare the size based on group and period

We know that the atomic size increases down the group and decreases from left to right across a period. Comparing the given elements, we see that Be is the smallest due to being in Period 2, and Rb is the largest due to being in Period 5.

Arrange the atoms in order of increasing size

Based on the analysis, the order of increasing size is: \[\mathrm{Be} < \mathrm{Na} < \mathrm{Rb}.\] b. Arrange the atoms \(\mathrm{Sr}, \mathrm{Se}, \mathrm{Ne}\) in order of increasing size.

Determine the position of elements in the periodic table

Sr is in Group 2 and Period 5, Se is in Group 16 and Period 4, and Ne is in Group 18 and Period 2.

Compare the size based on group and period

Comparing the given elements, we see that Ne is the smallest due to being in Period 2, and Sr is the largest due to being in Period 5.

Arrange the atoms in order of increasing size

Based on the analysis, the order of increasing size is: \[\mathrm{Ne} < \mathrm{Se} < \mathrm{Sr}.\] c. Arrange the atoms \(\mathrm{Fe}, \mathrm{P}, \mathrm{O}\) in order of increasing size.

Determine the position of elements in the periodic table

Fe is in Group 8 and Period 4, P is in Group 15 and Period 3, and O is in Group 16 and Period 2.

Compare the size based on group and period

Comparing the given elements, we see that O is the smallest due to being in Period 2, and Fe is the largest due to being in Period 4.

Arrange the atoms in order of increasing size

Based on the analysis, the order of increasing size is: \[\mathrm{O} < \mathrm{P} < \mathrm{Fe}.\] So, the order of increasing size is as follows: a. \(\mathrm{Be} < \mathrm{Na} < \mathrm{Rb}\) b. \(\mathrm{Ne} < \mathrm{Se} < \mathrm{Sr}\) c. \(\mathrm{O} < \mathrm{P} < \mathrm{Fe}\)