Interaction of methane with oxygen – combustion reaction

The simplest representative of the alkanes

[Deposit Photos]

Meth­ane is a gaseous com­pound with the chem­i­cal for­mu­la of CH₄. Meth­ane has no smell or taste, and is a non-tox­ic sub­stance. The flamma­bil­i­ty lim­it of the gas is a con­cen­tra­tion in air from 5 to 15%.

Main char­ac­ter­is­tics of meth­ane

Meth­ane is the sim­plest rep­re­sen­ta­tive of the alka­nes. This group of or­gan­ic com­pounds is called sat­u­rat­ed or paraf­fin hy­dro­car­bons. They have a sim­ple bond be­tween the car­bon atoms in the mol­e­cule, and the oth­er va­len­cies of each car­bon atom are sat­u­rat­ed with hy­dro­gen atoms. The most im­por­tant re­ac­tion of alka­nes is com­bus­tion. Alka­nes burn with the for­ma­tion of wa­ter va­por and gaseous car­bon diox­ide. As a re­sult of this re­ac­tion, chem­i­cal en­er­gy is re­leased in huge quan­ti­ties, which can be trans­formed into elec­tri­cal or ther­mal en­er­gy.

Molecule of methane [Wikimedia]

The com­bus­tion of meth­ane is used to ob­tain com­bus­tion gas­es, which pro­vide en­er­gy to pow­er gas tur­bines. In many places, meth­ane is sup­plied to hous­es in pipes and used for heat­ing and cook­ing. Com­pared with oth­er types of hy­dro­car­bon fuel, the com­bus­tion of nat­u­ral gas (meth­ane) is char­ac­ter­ized by the re­lease of a low­er amount of car­bon diox­ide and a greater amount of heat. Here you’ll find in­ter­est­ing ex­per­i­ments for learn­ing the prop­er­ties of dif­fer­ent gas­es.

Heating system [Deposit Photos]

Meth­ane with oxy­gen – com­bus­tion re­ac­tion

The process of the com­bus­tion of meth­ane is the in­ter­ac­tion of meth­ane with oxy­gen. As a re­sult of the re­ac­tion, wa­ter, car­bon diox­ide and a great deal of en­er­gy are formed. The re­ac­tion equa­tion of meth­ane com­bus­tion:

CH₄[gas] + 2O₂[gas] → CO₂[gas] + 2H₂O[steam] + 891kJ

Re­ac­tion de­scrip­tion

1 mol­e­cule of meth­ane in an in­ter­ac­tion with 2 mol­e­cules of oxy­gen forms 1 mol­e­cule of car­bon diox­ide and 2 mol­e­cules of wa­ter. In the re­ac­tion process heat en­er­gy is re­leased equiv­a­lent to 891 kJ. Nat­u­ral gas is the purest gas for burn­ing, which has a sim­ple com­po­si­tion and does not re­lease harm­ful chem­i­cals into the air. As nat­u­ral gas is 95% meth­ane, in its com­bus­tion hard­ly any byprod­ucts are formed, or far few­er byprod­ucts are formed than when oth­er types of fos­sil fuel are used.

Natural gas burns without soot [Flickr]

If you put a porce­lain pot lid in a meth­ane flame, a black de­posit of soot will not form, as the car­bon in the meth­ane burns com­plete­ly. A flame that leaves no soot is a qual­i­ta­tive re­ac­tion for sat­u­rat­ed hy­dro­car­bons.