Hi friend
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Your answer
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Water = H2O
Number of molecules in one mole of water = 6.022 × 10²³ [Avogadro's constant]
Given number of molecules = 2.52 × 10²³
So,
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Number of moles =
[tex] \frac{2.52 \times 10 {}^{24} }{6.022 \times 10 {}^{23} } \\ \\ = 4.184 \: (approximately)[/tex]
HOPE IT HELPS