The moles of water in 45.9 g is 2.54 mol.
The moles are defined as the mass of substance with respect to the molar mass. The moles of sample are given by:
[tex]\rm Moles=\dfrac{Mass}{Molar\;mass}[/tex]
The molar mass is the sum of mass of each element in the formula unit. The molar mass of water is 18.02 g/mol.
The given mass of water is 45.9 g.
Substitute the values for the moles of water:
[tex]\rm Moles=\dfrac{45.9 \;g}{18. 02 \;g/mol}\\\\ Moles=2.54\;mol[/tex]
The moles of water in 45.9 g is 2.54 mol.
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