Borax bead test is not given by

Options

A. Copper salts
B. Cobalt salts
C. Nickel salts
D. Aluminium salts

Answer

To solve the question "Borax bead test is not given by," we need to analyze the properties of the salts provided in the options and determine which one does not produce a colored borax bead.

### Step-by-Step Solution:

1. **Understand the Borax Bead Test**:
- The borax bead test is a qualitative analysis method used to identify certain metal ions based on the color of the bead formed when the metal salt is heated with borax (sodium tetraborate).
- The test is indicative of the metal's ability to produce a colored bead, which is typically associated with transition metals.

2. **Identify the Salts**:
- We need to consider the salts mentioned in the options. Common examples include salts of copper, cobalt, nickel, and aluminum.

3. **Analyze Each Salt**:
- **Copper Salt**: Copper salts (like copper(II) sulfate) produce a sky blue color when subjected to the borax bead test.
- **Cobalt Salt**: Cobalt salts (like cobalt(II) chloride) yield a deep blue color in the borax bead test.
- **Nickel Salt**: Nickel salts (like nickel(II) sulfate) give a yellow-brown color when tested.
- **Aluminum Salt**: Aluminum salts (like aluminum sulfate) are colorless and do not produce a colored bead.

4. **Determine Which Salt Does Not Give the Test**:
- From our analysis, we see that copper, cobalt, and nickel salts all produce colored beads. However, aluminum salts are colorless and therefore do not give a borax bead test.

5. **Conclusion**:
- The salt that does not give the borax bead test is **Aluminum Salt**.

### Final Answer:
The correct option for the question is **Aluminum Salt**.