Question

Calculate the number of molecules present in 0.9g of water.

Answer 1

here is your answer...

Answer 2

1 molecular gram contains 6.023 × 10²³ molecules.

1 molecular gram of water

H = 1

O = 16

So , H₂O

= 1 × 2 + 16

= 18

Hence 18 g of water will have 6.023 × 10²³ molecules.

Hence 1 g of water will have 6.023 × 10²³ / 18 molecules

Thus 0.9 g of water will have 6.023 × 10²³ / 18 × 0.9 molecules

==> 6.023× 10²³× 0.05

The number of molecules is 0.05×  6.023× 10²³

Hope it helps :-)

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