1 Write the correct symbol, with both superscript and subscript, for each of the following. Use the list of elements in the front
inside cover as needed: (a) the isotope of platinum that contains
118 neutrons, (b) the isotope of krypton with mass number 84,
(c) the isotope of arsenic with mass number 75, (d) the isotope of
magnesium that has an equal number of protons and neutrons.

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.