Question

When 3.00 grams of methane, CH,, reacts according to the balanced equation below, how many molecules of water are produced?

CH, + 202 - CO2 + 2H20

Answer 1

2.41×10²³ molecules of water

Step-by-step explanation:

Given data:

Mass of methane = 3 g

Molecules of water formed = ?

Solution:

Chemical equation:

CH₄ + 2O₂ → CO₂ + 2H₂O

Number of moles of methane:

Number of moles = mass/ molar mass

Number of moles = 3 g/ 16 g/mol

Number of moles = 0.2 mol

Now we will compare the moles of water with methane.

CH₄ : 2H₂O

1 : 2

0.2 : 2 × 0.2 = 0.4 mol

Molecules of water:

1 mole = 6.022×10²³ molecules of water

0.4 mol ×6.022×10²³ molecules of water / 1mol

2.41×10²³ molecules of water