The substance that will have more particles is 1 g of oxygen.
But
Therefore,
18 g of water = 6.02×10²³ particles
Therefore,
1 g of water = (1 × 6.02×10²³) / 18
1 g of water = 3.34×10²² particles
16 g of water = 6.02×10²³ particles
Therefore,
1 g of oxygen = (1 × 6.02×10²³) / 16
1 g of oxygen = 3.76×10²² particles
From the above, we can conclude that 1 g of oxygen contains more particles than 1 g of water
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