The percentage of lanthanides and iron, respectively , in which metal are

Options

A. 50 , 50
B. 75 , 25
C. 90, 10
D. 95, 5

Answer

To solve the question regarding the percentage of lanthanides and iron in mish metal, we will follow these steps:

### Step-by-Step Solution:

1. **Understand the Composition of Mish Metal**:
Mish metal is an alloy primarily composed of rare earth elements, particularly lanthanides, and some iron.

2. **Identify the Given Percentages**:
According to the information provided, mish metal contains:
- 50% of a component (let’s denote it as CDM, which could refer to a specific lanthanide).
- 45% of lanthanum (which is a lanthanide).

3. **Calculate the Total Percentage of Lanthanides**:
Since both CDM and lanthanum are part of the lanthanide group, we can add their percentages together:
\[ \text{Total percentage of lanthanides} = 50\% + 45\% = 95\% \]

4. **Determine the Percentage of Iron**:
To find the percentage of iron in mish metal, we subtract the total percentage of lanthanides from 100%:
\[ \text{Percentage of iron} = 100\% - 95\% = 5\% \]

5. **Final Result**:
Therefore, the percentages of lanthanides and iron in mish metal are:
- Lanthanides: 95%
- Iron: 5%

### Conclusion:
The answer to the question is that the percentage of lanthanides in mish metal is 95%, and the percentage of iron is 5%.