Which of the following correctly represents 360 g of water?
(i) 2 moles of `H_(2)O`
ii) 20 moles of water.
iii) `6.022 xx 10^(23)` molecules of water.
iv) `1.2044 xx 10^(25)` molecules of water.

Options

A. only (i)
B. (i) and (iv)
C. (ii) and (iii)
D. (ii) and (iv)

Answer

D

Explanation

(ii) and (iv) points correctly represent 360g of water.
ii) From point,
`therefore` 1 mole of water = molar mass of water =18 g
`therefore` 20 moles of water =18g `xx`20g =360g
iv) From point,
`therefore 6.022 xx 10^(23)` molecules of water = 1 mole = 18g of water.
`therefore 1.2044 xx 10^(25)` molecules of water `=(18g xx 1.2044 xx 10^(25))/(6.022 xx 10^(23)) = 360g`
Therefore, point (ii) and (iv) represent 360g of water.
Students can check other point also, as
i) 1 mole of water = molar mass of water =18 g of water.
`therefore` 2 mole of water =`18 xx 2=36`g
iii) `6.022 xx 10^(23)` molecules of water = 18g water.