Total number of inner transition elements are :- `W, Ru, U, Tc, La ,Yb, Po, No`

Answer

To determine the total number of inner transition elements from the given list (W, Ru, U, Tc, La, Yb, Po, No), we need to identify which of these elements belong to the f-block of the periodic table. The f-block elements are known as inner transition elements and include the lanthanides and actinides series.

### Step-by-Step Solution:

1. **Identify the Elements**: We have the following elements:
- W (Tungsten)
- Ru (Ruthenium)
- U (Uranium)
- Tc (Technetium)
- La (Lanthanum)
- Yb (Ytterbium)
- Po (Polonium)
- No (Nobelium)

2. **Determine the Atomic Numbers**:
- W (Tungsten) - Atomic Number 74
- Ru (Ruthenium) - Atomic Number 44
- U (Uranium) - Atomic Number 92
- Tc (Technetium) - Atomic Number 43
- La (Lanthanum) - Atomic Number 57
- Yb (Ytterbium) - Atomic Number 70
- Po (Polonium) - Atomic Number 84
- No (Nobelium) - Atomic Number 102

3. **Write the Electronic Configurations**:
- W: [Xe] 6s² 4f¹⁴ 5d⁴
- Ru: [Kr] 5s¹ 4d⁵
- U: [Rn] 7s² 5f³ 6d¹
- Tc: [Kr] 5s² 4d⁵
- La: [Xe] 6s² 5d¹
- Yb: [Xe] 6s² 4f¹⁴
- Po: [Rn] 6s² 4f¹⁴ 5d¹⁰ 6p⁴
- No: [Rn] 7s² 5f¹⁴

4. **Identify Inner Transition Elements**:
- Inner transition elements are characterized by having their outermost electrons filling the f-orbital.
- From the configurations:
- W: Last electron in 5d (not an inner transition element)
- Ru: Last electron in 4d (not an inner transition element)
- U: Last electron in 5f (is an inner transition element)
- Tc: Last electron in 4d (not an inner transition element)
- La: Last electron in 5d (not an inner transition element)
- Yb: Last electron in 4f (is an inner transition element)
- Po: Last electron in 6p (not an inner transition element)
- No: Last electron in 5f (is an inner transition element)

5. **Count the Inner Transition Elements**:
- The inner transition elements identified are:
- U (Uranium)
- Yb (Ytterbium)
- No (Nobelium)

Thus, the total number of inner transition elements from the given list is **3**.

### Final Answer:
**Total number of inner transition elements = 3**