Pr, Nd, Tb & Dy show +4 oxidation state in the form of -

Options

A. Chromates & Halides
B. Mangnate & Chromate
C. Both of the above
D. Oxide

Answer

To determine the form in which Praseodymium (Pr), Neodymium (Nd), Terbium (Tb), and Dysprosium (Dy) show a +4 oxidation state, we can follow these steps:

### Step 1: Understand the Elements
Pr, Nd, Tb, and Dy are all part of the lanthanide series in the periodic table. They are known for their unique properties and oxidation states.

**Hint:** Remember that these elements belong to the lanthanide series, which is crucial for understanding their oxidation states.

### Step 2: Common Oxidation States
The most common oxidation state for lanthanides is +3. However, some of these elements can exhibit a +4 oxidation state under certain conditions.

**Hint:** Keep in mind that while +3 is common, +4 is less frequent and requires specific conditions.

### Step 3: Conditions for +4 Oxidation State
For lanthanides to exhibit a +4 oxidation state, a strong anion must be present. This is typically seen in compounds where these elements are bonded to oxygen.

**Hint:** Think about the types of compounds that can stabilize higher oxidation states, particularly those involving oxygen.

### Step 4: Identify the Form
The +4 oxidation state for Pr, Nd, Tb, and Dy is primarily found in their oxides. Therefore, the correct form in which these elements show a +4 oxidation state is in oxides.

**Hint:** Consider the common compounds formed by these elements and focus on oxides as a key example.

### Conclusion
Thus, Pr, Nd, Tb, and Dy show a +4 oxidation state in the form of oxides.

**Final Answer:** Oxides