Methane reacts with oxygen according to the following equation. CH2(g) + 2O2(g) -------> CO2(g) + 2H2O(l)

Question

Methane reacts with oxygen according to the following equation.

CH2(g) + 2O2(g)   ------->      CO2(g) + 2H2O(l)

The ff data were obtained from an experiment.

Time (min)	[CH4] (mol L-1)	[CO2] (mol L-1)
0	0.050	0
10	0.030	0.020
20	0.020	?
30	0.015	?

1. How many moles of CO2 are produced for each mole of CH4 that is used up?
2. What concentration of CH4 is used up after 10 minutes?
3. What is the concentration of carbon dioxide after 20 minutes?
4. Write an equation for reaction rate in terms of [CO2].

Answer 1

CH4(g) + 2O2(g)  ==>   CO2(g) + 2H2O(l) (you wrote CH2 but meant CH4)

1). How many moles of CO2 are produced for each mole of CH4 that is used up?

1 mol CH4 x 1 mol CO2 / mol CH4 = 1 mole CO2

2). What concentration of CH4 is used up after 10 minutes?

Initial [CH4] = 0.05 M

After 10 min, [CH4] = 0.03 M

[CH4] used up after 10 min = 0.05 - 0.03 = 0.02 M

3). What is the concentration of carbon dioxide after 20 minutes?

[CH4] used up after 20 min = 0.05 - 0.02 = 0.03 M

[CO2] after 20 min = 0.03 M

4). Write an equation for reaction rate in terms of [CO2].

rate = ∆[CO2] / ∆t