Read the following passage and answer the questions based on it.

The transition metals are very hard and have low volatility. Their melting and boiling points are high. In any row, the melting points of these metals rise to a maximum at $d^5$ and fall regularly as atomic number increases. The high melting points of these metals are attributed to the involvement of greater number of electrons from (n-1)d in addition to ns electrons in the interatomic metallic bonding.

Which transition metal has the highest melting point?

W

The correct answer is Option (3) → W.

To determine which transition metal has the highest melting point among Hafnium (Hf), Tantalum (Ta), Tungsten (W), and Rhenium (Re), let's look at the melting points of these metals.

Melting Points of the Transition Metals

1. Hafnium (Hf):

Melting Point: Approximately 2,233 °C

Properties: Hafnium is known for its high melting point and resistance to corrosion, making it suitable for nuclear applications.

2. Tantalum (Ta):

Melting Point: Approximately 3,017 °C

Properties: Tantalum has excellent corrosion resistance and is used in electronics and surgical implants.

3. Tungsten (W):

Melting Point: Approximately 3,422 °C

Properties: Tungsten has the highest melting point of all metals and is often used in applications that require materials to withstand high temperatures, such as light bulb filaments and aerospace components.

4. Rhenium (Re):

Melting Point: Approximately 3,186 °C

Properties: Rhenium has a very high melting point and is used in high-temperature superalloys and as a catalyst in certain chemical reactions.

Conclusion

Among the metals listed, Tungsten (W) has the highest melting point at approximately 3,422 °C.

Thus, the correct answer is: W (Tungsten).