Which of the following weighs most?

Options

A. 2 g atoms of nitrogen
B. 25g iron
C. `2 xx 10^(23)` atoms of carbon
D. 22.4 L of `CO_(2)` at STP

Explanation

To determine which of the given options weighs the most, we need to calculate the mass of each option in grams. Let's break down the calculations step by step.

### Step 1: Calculate the mass of 2 g atoms of Nitrogen
- **Given:** 2 g atoms of nitrogen.
- **Molar Mass of Nitrogen (N):** Approximately 14 g/mol.
- **Calculation:**
- 2 g atoms of nitrogen means 2 moles of nitrogen.
- Mass = Moles × Molar Mass = 2 moles × 14 g/mol = 28 g.

### Step 2: Calculate the mass of 2 x 10^23 atoms of Carbon
- **Given:** 2 x 10^23 atoms of carbon.
- **Molar Mass of Carbon (C):** Approximately 12 g/mol.
- **Avogadro's Number:** 6.022 x 10^23 atoms/mol.
- **Calculation:**
- Number of moles = (2 x 10^23 atoms) / (6.022 x 10^23 atoms/mol) = 0.332 moles.
- Mass = Moles × Molar Mass = 0.332 moles × 12 g/mol = 3.984 g (approximately 4 g).

### Step 3: Calculate the mass of 22.4 liters of CO2 at STP
- **Given:** 22.4 liters of CO2 at STP.
- **Molar Volume at STP:** 22.4 liters/mol.
- **Molar Mass of CO2:** 12 g (C) + 16 g (O) × 2 = 44 g.
- **Calculation:**
- Number of moles = Volume / Molar Volume = 22.4 liters / 22.4 liters/mol = 1 mole.
- Mass = Moles × Molar Mass = 1 mole × 44 g/mol = 44 g.

### Step 4: Compare the masses
- Mass of 2 g atoms of Nitrogen = 28 g.
- Mass of 2 x 10^23 atoms of Carbon = 4 g.
- Mass of 22.4 liters of CO2 = 44 g.

### Conclusion
The heaviest option is 22.4 liters of CO2 at STP, which weighs 44 g.

### Final Answer
**The option that weighs the most is 22.4 liters of CO2 at STP (44 g).**

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