Mendeleev's periodic law states that the properties of element are periodic function of their

Options

A. Reactivity of elements
B. atoms size
C. atomic mass
D. electronic configuration

Explanation

To solve the question regarding Mendeleev's periodic law, we can break it down into the following steps:

### Step 1: Understand Mendeleev's Periodic Law
Mendeleev's periodic law states that the properties of elements are a periodic function of their atomic masses. This means that when elements are arranged in order of increasing atomic mass, elements with similar properties appear at regular intervals.

### Step 2: Identify Key Terms
- **Periodic Law**: A principle that describes the recurring trends in the properties of elements when they are arranged by atomic mass.
- **Atomic Mass**: The mass of an atom, typically measured in atomic mass units (amu), which is a key factor in Mendeleev's arrangement of elements.

### Step 3: Mendeleev's Contribution
Dmitri Mendeleev was a Russian chemist who developed one of the first periodic tables. He organized elements based on their atomic masses and noted that elements with similar chemical properties appeared at regular intervals.

### Step 4: Conclusion
Based on Mendeleev's observations and the definition of his periodic law, we conclude that the properties of elements are periodic functions of their atomic masses.

### Final Answer
Mendeleev's periodic law states that the properties of elements are periodic functions of their **atomic masses**.

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