Which of the following series of elements have nearly the same atomic radii

Options

A. F,Cl,Br,I
B. Na,K,Rb,Cs
C. Li,Be,B,C
D. Fe,Co,Ni,Cu

Answer

To determine which series of elements have nearly the same atomic radii, we can follow these steps:

### Step 1: Understand Atomic Radii
Atomic radius is the distance from the nucleus of an atom to the outermost shell of electrons. It generally decreases across a period and increases down a group in the periodic table.

### Step 2: Identify the Series of Elements
The question asks for a series of elements. We need to consider the series of elements provided in the options (not given in the question, but typically they would be groups of elements).

### Step 3: Focus on Transition Metals
From the video transcript, it is mentioned that transition metals (the d-block elements) exhibit a trend of nearly constant atomic radii. This is particularly true for the 3d series of transition metals, which includes the following elements:
- Scandium (Sc)
- Titanium (Ti)
- Vanadium (V)
- Chromium (Cr)
- Manganese (Mn)
- Iron (Fe)
- Cobalt (Co)
- Nickel (Ni)
- Copper (Cu)
- Zinc (Zn)

### Step 4: Analyze the Atomic Radii Trend
In the case of the 3d transition series, the atomic radius decreases up to manganese (Mn) and then remains nearly constant from iron (Fe) to copper (Cu). This means that the atomic radii of iron, cobalt, nickel, and copper are very similar.

### Step 5: Conclusion
Based on the analysis, the series of elements that have nearly the same atomic radii is:
- Iron (Fe), Cobalt (Co), Nickel (Ni), and Copper (Cu).

### Final Answer
The series of elements that have nearly the same atomic radii is Iron (Fe), Cobalt (Co), Nickel (Ni), and Copper (Cu).

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