MCQ Detailed View

The number of atoms in one mole of a substance depends on how many atoms are present in a single molecule of that substance. Since 1 mole = 6.022 × 10²³ molecules (Avogadro’s number), the molecule that has more atoms per molecule will have the highest total number of atoms per mole.

Let’s calculate the total atoms for each option:

1️⃣ H₂SO₄ (Sulfuric acid)

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  Composition: 2 Hydrogen (H) + 1 Sulfur (S) + 4 Oxygen (O)

  
  


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  Total atoms per molecule = 2 + 1 + 4 = 7 atoms

  
  

2️⃣ HClO₄ (Perchloric acid)

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  Composition: 1 Hydrogen (H) + 1 Chlorine (Cl) + 4 Oxygen (O)

  
  


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  Total atoms = 1 + 1 + 4 = 6 atoms

  
  

3️⃣ O₃ (Ozone)

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  Composition: 3 Oxygen atoms

  
  


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  Total atoms = 3 atoms

  
  

4️⃣ H₂C₂O₄ (Oxalic acid)

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  Composition: 2 Hydrogen (H) + 2 Carbon (C) + 4 Oxygen (O)

  
  


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  Total atoms = 2 + 2 + 4 = 8 atoms

  
  

✅ Result:

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  H₂C₂O₄ has the highest number of atoms per molecule (8 atoms).

  
  


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  Therefore, 1 mole of H₂C₂O₄ contains:
  8 atoms×6.022×1023=4.8176×10248 \text{ atoms} \times 6.022 × 10^{23} = 4.8176 × 10^{24}8 atoms×6.022×1023=4.8176×1024 atoms

  
  

This is higher than all other molecules given in the options.

Key Concept Recap:

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  1 mole = 6.022 × 10²³ molecules of any substance.

  
  


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  The total number of atoms in 1 mole = (Atoms per molecule) × (Avogadro’s number).

  
  


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  More atoms per molecule = More total atoms per mole.

  
  

Thus, H₂C₂O₄ (Oxalic acid) contains the maximum number of atoms per mole among the given choices.