Question

The element that does not belong to the same period of the remaining elements (modern periodic table) is:

• A. Palladium
• B. Iridium
• C. Osmium
• D. Platinum

Hint:

When analyzing elements in the periodic table, always check their atomic number to determine their period. Elements in the same period have the same number of electron shells.

Answer 1

The Correct Option is A

The question asks to identify the element that does not belong to the same period as the others in the modern periodic table. Let's analyze the given elements one by one: 

1. Palladium (Pd): Palladium is an element in the 5th period of the periodic table, and it is found in Group 10.
2. Iridium (Ir): Iridium belongs to the 6th period and is found in Group 9.
3. Osmium (Os): Osmium is located in the 6th period and belongs to Group 8.
4. Platinum (Pt): Platinum is also in the 6th period, found in Group 10.

From this analysis, we observe:

• Iridium, Osmium, and Platinum all belong to the 6th period of the periodic table.
• Palladium, on the other hand, belongs to the 5th period.

Therefore, the element only belonging to the 5th period and differing from the rest is Palladium (Pd).

Conclusion: The element that does not belong to the same period as the remaining elements is Palladium, which is the correct answer.

Answer 2

In the modern periodic table, elements are arranged in periods (rows) based on their atomic numbers. To determine which element does not belong to the same period as the others, we need to identify the periods of the given elements:
 

• Palladium (Pd): atomic number 46, located in period 5.
• Iridium (Ir): atomic number 77, located in period 6.
• Osmium (Os): atomic number 76, located in period 6.
• Platinum (Pt): atomic number 78, located in period 6.

The elements Iridium, Osmium, and Platinum are all in period 6. Palladium, however, is in period 5, making it the element that does not belong to the same period as the others. Therefore, Palladium is the correct answer.