Choose the wrong statement.
1. 1 mole means `6.023 xx 10^(23)` particles
2. Molar mass is mass of one molecule
3. Molar mass is mass of one mole of substance
4. Molar mass is molecular mass expressed in grams

Options

A. 1 mole means `6.023 xx 10^(23)` particles
B. Molar mass is mass of one molecule
C. Molar mass is mass of one mole of substance
D. Molar mass is molecular mass expressed in grams

Explanation

To solve the problem of identifying the wrong statement among the given options, we will analyze each statement one by one.

### Step 1: Analyze Statement 1
**Statement:** 1 mole means `6.023 x 10^(23)` particles.

**Analysis:**
This statement is correct. By definition, 1 mole of any substance contains Avogadro's number of particles, which is approximately `6.023 x 10^(23)`.

### Step 2: Analyze Statement 2
**Statement:** Molar mass is mass of one molecule.

**Analysis:**
This statement is incorrect. Molar mass is defined as the mass of one mole of a substance (which is `6.023 x 10^(23)` molecules for a molecular substance), not the mass of a single molecule. The mass of one molecule is referred to as molecular mass or molecular weight.

### Step 3: Analyze Statement 3
**Statement:** Molar mass is mass of one mole of substance.

**Analysis:**
This statement is correct. Molar mass is indeed defined as the mass of one mole of a substance, measured in grams per mole (g/mol).

### Step 4: Analyze Statement 4
**Statement:** Molar mass is molecular mass expressed in grams.

**Analysis:**
This statement is also correct. Molar mass is the molecular mass (which is typically expressed in atomic mass units) converted to grams per mole.

### Conclusion
After analyzing all statements, we find that the wrong statement is **Statement 2**: "Molar mass is mass of one molecule."

### Final Answer
**The wrong statement is:** 2. Molar mass is mass of one molecule.

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