calculate the relative atomic mass of calcium given that the number of moles in 0.4 moles and mass is 16 g

The relative atomic mass of Calcium : 40 g/mol

The mole is the number of particles contained in a substance

1 mol = 6.02.10²³

Moles can also be determined from the amount of substance mass and its molar mass / the relative atomic mass(Ar) :

Calcium (Ca) :  

moles = 0.4

mass = 16 g

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.