1.What mass of oxygen gas, O2, from the air is consumed in the combustion of 702g of octane, C8H18, one of the principal components of gasoline? 2C8H18 + 25O2 -> 16CO2 + 18H2O.

Approximately .

Explanation:

Look up the following relative atomic mass values on a modern periodic table:

Calculate the molar mass of octane, :

.

Similarly, calculate the molar mass of :

.

How many moles of molecules in of octane, ?

.

Make sure that the chemical equation here is balanced.

In this equation,

Ratio between the two coefficients:

.

Therefore:

.

Rearrange to obtain:

.

It is already determined that . Hence, the number of moles of oxygen gas required will be:

.

What would be the mass of that of ?

.

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.