The chemical reaction in this example is of environmental interest. Iron pyrite (Fesz) is often an impurity in
coal, and so burning this fuel in a power plant produces sulfur dioxide (SO), a major air pollutant.
Calculate the mass of sulfur dioxide (SO2) produced when 3.84 mol O2 is reacted with Fes, according to the
equation
4 FeSacs + 11 O.
- 2 Fe2O3(-) + S SO2(e)

178.87 grams of sulphur dioxide is formed according to the  equation given.

Explanation:

The balanced chemical reaction for the process is:

4 FeS2 + 11 O2 ⇒ 2Fe2O3(-) + 8 SO2

the reaction involving FeS and oxygen having balanced chemical equation as:

moles of oxygen given as 3.84

so when  11 moles of O2 reacts to form 8 moles SO2

                3.84 moles of oxygen reacts to form x moles of SO2

=

x =

2.792 moles of sulphur dioxide will be formed

The mass can be calculated as number of moles x molar mass of 1 mole of SO2

= 2.792 x 64.066

= 178.87 grams of sulphur dioxide is formed.

on passing the small ampere of electric current through the tube made of ar and hg of cfl generates uv rays which excites the fluorescent and thus emits the high radiation by consumption of just 5- 12 w in comparison to incandescent light which requires more power such as around 40 - 55 w to lighten.

moreover the life span of fluorescent or cfl is around 8000 h whereas the life span of incandescent is around 1200 h

hence, the building installed with incandescent lights bears more electricity bill.