The very first element similar to lithium according to law of octave is

Options

A. sodium
B. potassium
C. boron
D. neon

Answer

To find the first element similar to lithium according to the law of octaves, we can follow these steps:

### Step 1: Understand the Law of Octaves
The law of octaves, proposed by John Newlands, states that when elements are arranged in order of increasing atomic mass, every eighth element has similar properties to the first one.

### Step 2: Identify Lithium
Lithium (Li) is the first element we are considering. It is the third element in the periodic table with an atomic number of 3.

### Step 3: List the Elements Following Lithium
According to the periodic table, the elements following lithium in order of increasing atomic mass are:
- Beryllium (Be)
- Boron (B)
- Carbon (C)
- Nitrogen (N)
- Oxygen (O)
- Fluorine (F)
- Sodium (Na)

### Step 4: Apply the Law of Octaves
Now, according to the law of octaves, if lithium is the first element, the eighth element in the series will have similar properties. Counting from lithium:
1. Lithium (Li)
2. Beryllium (Be)
3. Boron (B)
4. Carbon (C)
5. Nitrogen (N)
6. Oxygen (O)
7. Fluorine (F)
8. Sodium (Na)

### Step 5: Conclusion
The eighth element after lithium is sodium (Na). Therefore, according to the law of octaves, sodium is the first element similar to lithium.

### Final Answer
The very first element similar to lithium according to the law of octaves is Sodium (Na).

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