Which of these substances contains the most total atoms per molecule?

A. [tex]Na_2PFO_3[/tex]

B. [tex]H_2SO_4[/tex]

C. [tex]Ni \left( NO_3 \right)_2[/tex]

D. [tex]NbCl_5[/tex]



Answer :

To determine which substance contains the most total atoms per molecule, let's analyze each chemical formula step by step and count the number of atoms present.

1. Sodium fluorooxophosphate, [tex]\( \text{Na}_2\text{PFO}_3 \)[/tex]:
- [tex]\( \text{Na}_2 \)[/tex]: This part has 2 sodium (Na) atoms.
- [tex]\( \text{P} \)[/tex]: This part has 1 phosphorus (P) atom.
- [tex]\( \text{F} \)[/tex]: This part has 1 fluorine (F) atom.
- [tex]\( \text{O}_3 \)[/tex]: This part has 3 oxygen (O) atoms.
- Total atoms: [tex]\( 2 + 1 + 1 + 3 = 7 \)[/tex]

2. Sulfuric acid, [tex]\( \text{H}_2\text{SO}_4 \)[/tex]:
- [tex]\( \text{H}_2 \)[/tex]: This part has 2 hydrogen (H) atoms.
- [tex]\( \text{S} \)[/tex]: This part has 1 sulfur (S) atom.
- [tex]\( \text{O}_4 \)[/tex]: This part has 4 oxygen (O) atoms.
- Total atoms: [tex]\( 2 + 1 + 4 = 7 \)[/tex]

3. Nickel(II) nitrate, [tex]\( \text{Ni}\left(\text{NO}_3\right)_2 \)[/tex]:
- [tex]\( \text{Ni} \)[/tex]: This part has 1 nickel (Ni) atom.
- [tex]\( \left(\text{NO}_3\right)_2 \)[/tex]: This means we have 2 nitrate groups, each containing 1 nitrogen (N) atom and 3 oxygen (O) atoms.
- For 2 nitrate groups: [tex]\( 2 \times (\text{N}_1 + \text{O}_3) = 2 \times (1 + 3) = 2 \times 4 = 8 \)[/tex] atoms.
- Total atoms: [tex]\( 1 + 2 + 6 = 5 \)[/tex]

4. Niobium pentachloride, [tex]\( \text{NbCl}_5 \)[/tex]:
- [tex]\( \text{Nb} \)[/tex]: This part has 1 niobium (Nb) atom.
- [tex]\( \text{Cl}_5 \)[/tex]: This part has 5 chlorine (Cl) atoms.
- Total atoms: [tex]\( 1 + 5 = 6 \)[/tex]

After counting the total number of atoms for each substance:
- [tex]\( \text{Na}_2\text{PFO}_3 \)[/tex]: 7 atoms
- [tex]\( \text{H}_2\text{SO}_4 \)[/tex]: 7 atoms
- [tex]\( \text{Ni}\left(\text{NO}_3\right)_2 \)[/tex]: 5 atoms
- [tex]\( \text{NbCl}_5 \)[/tex]: 6 atoms

Both [tex]\( \text{Na}_2\text{PFO}_3 \)[/tex] and [tex]\( \text{H}_2\text{SO}_4 \)[/tex] contain the most atoms per molecule, with 7 atoms each. Therefore, the substances with the most total atoms per molecule are Na_2PFO_3 and H_2SO_4.