The property of hydrogen which distinguish it from other alkali metal is

Options

A. its reducing character
B. its electropositive character
C. its affinity for non-metal
D. its non-metallic character

Explanation

To determine the property of hydrogen that distinguishes it from other alkali metals, we can follow these steps:

### Step 1: Identify the Group
Hydrogen is often placed in Group 1 of the periodic table, which is known as the alkali metals group. The alkali metals include lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr).

**Hint:** Consider the position of hydrogen in the periodic table and its similarities with alkali metals.

### Step 2: Analyze the Properties of Hydrogen
Hydrogen has unique properties that set it apart from alkali metals. One significant property is its ability to act as both an electron donor and an electron acceptor. This means hydrogen can either lose its single electron to form a positive ion (H⁺) or gain an electron to achieve a stable configuration similar to that of helium (He).

**Hint:** Think about how hydrogen behaves chemically compared to other alkali metals.

### Step 3: Compare with Alkali Metals
While alkali metals predominantly exhibit metallic characteristics and tend to lose their outermost electron to form positive ions (cations), hydrogen can also gain an electron. This dual behavior allows hydrogen to participate in both oxidation and reduction reactions, which is not typical for alkali metals.

**Hint:** Focus on the oxidation and reduction capabilities of hydrogen versus the behavior of alkali metals.

### Step 4: Highlight Non-Metallic Character
One of the most distinguishing features of hydrogen is its non-metallic character. Unlike alkali metals, which are purely metallic and do not exhibit non-metallic behavior, hydrogen can form covalent bonds and exists as a diatomic molecule (H₂) under standard conditions. This non-metallic character allows hydrogen to form compounds with non-metals, such as water (H₂O) and hydrogen chloride (HCl).

**Hint:** Consider the types of bonds and compounds that hydrogen can form compared to alkali metals.

### Step 5: Conclusion
The property that distinguishes hydrogen from other alkali metals is its non-metallic character. While alkali metals are characterized by their metallic properties and behavior, hydrogen exhibits non-metallic properties, allowing it to form a variety of compounds that alkali metals cannot.

**Final Answer:** The property of hydrogen that distinguishes it from other alkali metals is its non-metallic character.

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