In order , increasing atomic size :Na,F,P,Ca ?
This link will help you understand the size vs where it is in the periodic table.
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjzz7a98sjpAhVCM6wKHai-DY0QwqsBMCR6BAgMEAw&url=https%3A%2F%2Fwww.khanacademy.org%2Fscience%2Fchemistry%2Fperiodic-table%2Fperiodic-table-trends-bonding%2Fv%2Fatomic-radius-trend&usg=AOvVaw0PazJWglO2noQBLfKFSmHn
When you finish you can check your work by looking up the radius or diameter of each element at this url.
https://www.webelements.com/
To determine the order of increasing atomic size for Na, F, P, and Ca, you need to compare the atomic radii of these elements. The atomic radius generally increases down a group and decreases across a period on the periodic table.
1. Sodium (Na) is located in Group 1 (Alkali Metals) and Period 3 on the periodic table. As you move down Group 1, the atomic radius increases due to the addition of more electron shells. Therefore, Na has a larger atomic radius compared to the other elements given.
2. Fluorine (F) is located in Group 17 (Halogens) and Period 2. As you move across Period 2, the atomic radius generally decreases because the increasing nuclear charge attracts the electrons closer to the nucleus. Therefore, F has a smaller atomic radius compared to Na.
3. Phosphorus (P) is located in Group 15 (Pnictogens) and Period 3. Similar to Na, as you move down Group 15, the atomic radius increases due to the addition of more electron shells. Therefore, P has a larger atomic radius compared to F.
4. Calcium (Ca) is located in Group 2 (Alkaline Earth Metals) and Period 4. As you move across Period 4, the atomic radius generally decreases due to the increasing nuclear charge. However, since Ca is in a different group than F, it will generally have a larger atomic radius.
Therefore, the order of increasing atomic size for Na, F, P, and Ca is: F < Ca < P < Na