Give me answer of this mcqs.

Dear student,

Please ask single question in single thread.

1) The molar mass of water is 18.
Thus, 18 g of water contains, Avogadro's number ($N_A$)of water molecule.
Therefore, 540 g of water will have $\frac{540}{18}\times N_A=30N_A$
​​​​Hydrogen has no neutrons and oxygen has 8 neutrons.
Water compose of two hydrogen atoms and one oxygen atom.
Thus total number of neutrons in each water molecule is 8.
Therefore, total number of neutrons in 540 g of water is,
$30N_A\times 8=240 N_A$
​​​Answer is a.

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