Which element is located in Group 2 (alkaline earth metals) and Period 3 of the periodic table?

• A. Calcium (Ca)
• B. Aluminum (Al)
• C. Magnesium (Mg)
• D. Sodium (Na)

Answer: (C)

Verified step by step guidance

1. Understand the layout of the periodic table: it is organized into groups (vertical columns) and periods (horizontal rows). Group 2 contains the alkaline earth metals.
2. Identify the elements in Group 2, which include Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), and Radium (Ra).
3. Locate Period 3 on the periodic table, which is the third horizontal row. Elements in Period 3 include Sodium (Na), Magnesium (Mg), Aluminum (Al), and others.
4. Find the element that is both in Group 2 and Period 3 by looking for the intersection of the second group and the third period. This element is Magnesium (Mg).
5. Confirm that Magnesium (Mg) fits the criteria of being an alkaline earth metal (Group 2) and located in Period 3, distinguishing it from Calcium (Ca) which is in Period 4, Aluminum (Al) which is in Group 13, and Sodium (Na) which is in Group 1.