Fusible alloys of lead with Bi and Si used for making soft solder , electric fuses, safety plug for boilers & automatic water sprinkles to prevent fire They melt at low temperature .

Options

A. Wood's metal
B. Lipowitzs alloy
C. Rose's metal
D. all of the above

Answer

To solve the question regarding fusible alloys of lead with bismuth and silicon, we need to identify which of the given options (Wood's metal, Lipovitz alloy, and Rose's metal) are indeed fusible alloys used for applications such as soft solder, electric fuses, safety plugs for boilers, and automatic water sprinklers.

### Step-by-Step Solution:

1. **Understanding Fusible Alloys**:
- Fusible alloys are mixtures of metals that melt at low temperatures. They are used in applications where a low melting point is essential, such as in safety devices and soldering.

2. **Identifying the Alloys**:
- The question provides three alloys: Wood's metal, Lipovitz alloy, and Rose's metal. We need to determine their compositions and melting points.

3. **Wood's Metal and Lipovitz Alloy**:
- Wood's metal is also known as Lipovitz alloy. They are the same alloy and are composed of:
- 50% Bismuth (Bi)
- 27.6% Lead (Pb)
- 13.3% Tin (Sn)
- 10% Cadmium (Cd)
- This alloy melts at a low temperature range of 73 to 77 degrees Celsius.

4. **Rose's Metal**:
- Rose's metal is another fusible alloy composed of:
- 50% Bismuth (Bi)
- 28% Lead (Pb)
- 20-25% Tin (Sn)
- It melts at a slightly higher low temperature range of 95 to 98 degrees Celsius.

5. **Conclusion**:
- Both Wood's metal (Lipovitz alloy) and Rose's metal are fusible alloys that meet the criteria mentioned in the question. Therefore, the answer to the question is that all of the given options are fusible alloys.

### Final Answer:
All of the above (Wood's metal, Lipovitz alloy, and Rose's metal) are fusible alloys.

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