Among the following elements, what is the total number of elements having the lowest oxidation state of zero? `
`Ta
`b.Te`
c. `Tc`
d. `Ti`
e. `TI`

Explanation

To determine the total number of elements among Ta, Te, Tc, Ti, and Tl that have the lowest oxidation state of zero, we can analyze each element based on its oxidation states.

### Step-by-Step Solution:

1. **Identify the Elements and Their Groups**:
- Ta (Tantalum) - Group 5
- Te (Tellurium) - Group 16
- Tc (Technetium) - Group 7
- Ti (Titanium) - Group 4
- Tl (Thallium) - Group 13

2. **Determine the Maximum Oxidation States**:
- The maximum oxidation state of an element is typically equal to its group number for metals.
- For non-metals, the maximum oxidation state can vary but is generally related to the number of valence electrons.

- Ta: +5 (Group 5)
- Te: +6 (Group 16)
- Tc: +7 (Group 7)
- Ti: +4 (Group 4)
- Tl: +3 (Group 13)

3. **Determine the Minimum Oxidation States**:
- For metals, the minimum oxidation state can be zero.
- For non-metals, the minimum oxidation state can be calculated as group number minus 8.

- Ta: 0 (can exhibit oxidation state of 0)
- Te: -2 (Group 16, minimum = 16 - 8 = -2)
- Tc: 0 (can exhibit oxidation state of 0)
- Ti: 0 (can exhibit oxidation state of 0)
- Tl: 0 (can exhibit oxidation state of 0)

4. **Count the Elements with Oxidation State of Zero**:
- From the analysis:
- Ta: 0
- Te: -2
- Tc: 0
- Ti: 0
- Tl: 0

- The elements with an oxidation state of zero are Ta, Tc, Ti, and Tl.

5. **Total Count**:
- Total number of elements with oxidation state of zero = 4 (Ta, Tc, Ti, Tl).

### Final Answer:
The total number of elements having the lowest oxidation state of zero is **4**.

---