Question

what volume of oxygen is required for the complete combustion of 15cm3 of ethane if all the gases measured at stp

Answer 1

First, let's write the combustion reaction of ethane equation:

2 C2H6 + 7 O2 --> 4 CO2 + 6 H2O

Now we need to transform 15 cm³ into liters.

1 cm³ ---- 0.001 liter

15 cm³ ---- x liter

x = 0.015 liters

We know that 1 mol of any gas in STP occupies the volume of 22.4L. So let's transform liters of ethane into mol.

1 mol --- 22.4 L

x mol --- 0.015 L

x = 6.696 x 10^-4 mol of C2H6

Now we use the equation ratio to find out the quantity of oxygen in moles:

2 mole C2H6 --- 7 mole O2

6.696 x 10^-4 mol of C2H6 --- x mol of O2

x = 2.34 x 10^-3 mol of O2

Now let's transform into liters:

2.34 x 10^-3 mol of O2 --- x liters

1 mol --- 22.4 L

x = 0.0525 liters or 52.5 cm³

Answer: The volume of oxygen required is 52.5 cm³.