Question

Ques. (2) How many molecule of H2O are three in 18g of water-

(1) 6.022 × 1024 (2) 6.022 × 1023

(3) 8.02 × 1023 (4) 7.02× 1023​

Answer 1

Answer:

i) 2 moles of water:

1 mole of water= molecular weight of water= 18 g of water

2 moles of water = 18×2=36 g of water.

ii) 20 moles of water:

1 mole of water= mol.wt of water= 18 g of water

20 moles of water=18×20=360 g of water

iii) 6.02×10.

23

molecules of water= mol.wt of water=18 g of water

iv) 6.02×10

23

molecules of water= mol.wt of water=18 g of water

1.2044×10

25

molecules of water=

6.02×10

23

1.2044×10

25

moles of water = 20 moles of water = 360 g of water.

Therefore option D (ii and iv) is correct.

Answer 2

Answer:

6.022 × 1023

Explanation:

Before respond to this issue , recall two things . 1 ) We will be required to find the molar mass of water . 2 ) We known that Avogadro 's number ( 6.022 X 10 twenty-three ) is atoms or molecules per mole . The molar mass of H 2 zero : ( 1.01 X 2 ) + ( 16.00 ) = 18.02 grams/mol Start with what you are given . 18 g H 2 zero X ( 1 mol H 2 O / 18.02 g H 2 O ) X ( 6.022 X 10 twenty-three molecules H 2 O / 1 mol H 2 O ) = 6.022 X 10 twenty-three molecules of H 2 O or 6.0 X 10 twenty-three if important figures count in your class