Upto which element, the Law of Octaves was found to be applicable ?

Options

A. Oxygen
B. Calcium
C. Cobalt
D. Potassium

Explanation

**Step-by-Step Solution:**

1. **Understanding 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. This means that the properties of the first element and the eighth element in the sequence will be alike.

2. **Identifying the Range of Applicability**: Newlands observed that this law was applicable primarily to lighter elements. As the atomic mass of the elements increased, deviations from this law became evident.

3. **Determining the Limit**: The law was found to be applicable up to the element with an atomic mass of 40. This atomic mass corresponds to the element calcium (Ca).

4. **Conclusion**: Therefore, the Law of Octaves was applicable up to calcium. Beyond this point, the properties of the elements did not follow the pattern established by the law.

5. **Final Answer**: The Law of Octaves was applicable up to the element calcium (Ca).

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