The element that is not present in misch metal is

Options

A. La
B. Iron
C. Na
D. Ce

Answer

To determine the element that is not present in misch metal, we can follow these steps:

### Step 1: Understand what misch metal is
Misch metal is an alloy primarily composed of rare-earth elements, specifically lanthanides, along with iron and small amounts of other elements.

### Step 2: Identify the main components of misch metal
The main components of misch metal include:
- Approximately 50% Cerium (Ce)
- About 25% Lanthanum (La)
- Small amounts of Neodymium (Nd), Praseodymium (Pr)
- Traces of Iron (Fe), Sulfur (S), Carbon (C), Calcium (Ca), and Aluminum (Al)

### Step 3: Analyze the options given
We need to analyze the options provided to identify which element is not present in misch metal. The options are:
1. Lanthanum (La)
2. Iron (Fe)
3. Sodium (Na)
4. Cerium (Ce)

### Step 4: Evaluate each option
- **Option 1: Lanthanum (La)** - Present in misch metal.
- **Option 2: Iron (Fe)** - Present in misch metal.
- **Option 3: Sodium (Na)** - Not present in misch metal.
- **Option 4: Cerium (Ce)** - Present in misch metal.

### Step 5: Conclusion
Based on the analysis, the element that is not present in misch metal is **Sodium (Na)**.

### Final Answer:
**Sodium (Na)** is the element that is not present in misch metal.

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