Place the following elements in order of increasing atomic radius. Ba < P < Cl P < Cl < Ba Cl < P < Ba Cl < Ba < P Ba < Cl < P
The Correct Answer and Explanation is:
To answer the question about the order of increasing atomic radius, let’s first look at the periodic trends. Atomic radius typically increases as you move down a group (column) of the periodic table and decreases as you move across a period (row) from left to right.
- Ba (Barium): Located in Group 2 and Period 6, barium has a large atomic radius because it is near the bottom of the periodic table. Elements at the bottom of the table have a larger radius due to having more electron shells.
- P (Phosphorus): Phosphorus is in Group 15 and Period 3. It is to the right of barium and has fewer electron shells. Being in Period 3, it will have a smaller atomic radius compared to elements like barium because of the stronger nuclear charge pulling the electrons closer to the nucleus.
- Cl (Chlorine): Chlorine is in Group 17 and Period 3, right next to phosphorus. It has a smaller atomic radius than phosphorus because it is further right on the periodic table, meaning more protons are pulling the electrons closer to the nucleus, resulting in a smaller radius.
Correct Order of Increasing Atomic Radius:
- Cl < P < Ba
Explanation: Chlorine has the smallest atomic radius due to its position on the right of the periodic table, where the atomic radius is smallest. Phosphorus comes next, as it is further left than chlorine but still in the same period. Barium, being in the first group (alkaline earth metals) and far down in the table, has the largest atomic radius due to its many electron shells and the weaker pull of the nucleus on the outermost electrons.
So, the correct choice is: Cl < P < Ba.
