Calculate the minimum volume of oxygen gas, at room temperature and pressure (r.t.p) required to completely burn 56g of methane gas

Respuesta :

Neetoo

Answer:

The volume of oxygen will be 168 dm³.

Explanation:

Given data:

mass of methane = 56 g

volume of oxygen = ?

Solution:

First of all we will write the balance chemical equation.

CH₄ + 2O₂ → CO₂ + 2H₂O

Now we will calculate the moles of methane:

number of moles = mass / molar mass

number of moles = 56 g / 16 g/mol

number of moles = 3.5 mol

Now we will compare the moles of oxygen and methane.

                                CH₄  :   O₂

                                   1     :     2  

                                 3.5   :    3.5 × 2 = 7

The moles of oxygen are 7 mol.

Now we will calculate the volume of oxygen. The gas is at room temperature and pressure so, one mole of gas will occupy 24 dm³ volume and 7 mole will occupy,

7 × 24 dm³ = 168 dm³

Answer: The volume of oxygen gas needed is 156.8 L

Explanation:

To calculate the number of moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]

Given mass of methane = 56 g

Molar mass of methane = 16 g/mol

Putting values in above equation, we get:

[tex]\text{Moles of methane}=\frac{56g}{16g/mol}=3.5mol[/tex]

The chemical equation for the combustion of methane follows:

[tex]CH_4+2O_2\rightarrow CO_2+2H_2O[/tex]

By Stoichiometry of the reaction:

1 mole of methane reacts with 2 moles of oxygen gas

So, 3.5 moles of methane will react with = [tex]\frac{2}{1}\times 3.5=7mol[/tex] of oxygen gas

At STP:

1 mole of a gas occupies 22.4 L of volume

So, 7 moles of oxygen gas occupies [tex]\frac{22.4}{1}\times 7=156.8L[/tex] of volume

Hence, the volume of oxygen gas needed is 156.8 L