Question

Question #8198e

Answer 1

7.48 g

Explanation:

Convert volume of methane in the balloon to moles:

Density methane = 0.716 g/L at STP
3.75 x 0.716 = 2.69 g of methane

Molar Mass `CH_4` = 16.04 g/mol

Using the equation: mol = mass / molar mass

Number of moles `CH_4` = 2.69 / 16.04
Number of moles `CH_4` = 0.17 mol

We need to write a balanced equation for this reaction to determine the molar ratio of `CO_2` and `CH_4`

`CH_4 + 2O_2 -> CO_2 + 2H_2O`

`CO_2` and `CH_4` in 1 : 1 ratio, so 0.17 moles of `CO_2` are produced in the combustion reaction.

Number of moles of `CO_2` = 0.17 mol
Molar mass `CO_2` = 44.01 g/mol

Rearranging the equation we used before: mass = mol x molar mass
Mass `CO_2` = 44.01 x 0.17
Mass `CO_2` = 7.48 g