Question

How many grams are there in 1.1 x 1027 molecules of water (H2O)?

Answer 1

Answer:

C) 3.3 x 104 grams

Explanation:

1 mole of water contains 6.02 × 10^23 atoms

1.1 × 10^27 atoms will contain;

1.1 × 10^27 ÷ 6.02 × 10^23

= 0.1827 × 10^( 27 - 23)

= 0.1827 × 10^(4)

= 1.827 × 10³ moles of water.

To convert mole to mass in grams, we use the formula;

mole (n) = mass (m) ÷ molar mass (MM)

Molar mas of water (H2O) = 1(2) of H + 16 of O = 18g/mol

mole = mass/molar mass

1.827 × 10³ = mass / 18

mass = 1.827 × 10³ × 18

mass = 32.886 × 10³

mass = 3.286 × 10⁴

mass = 3.3 × 10⁴ grams