Skip to main content

ISOTOPES

ISOTOPES 
The atoms of the same element having same atomic number but different atomic masses are called isotopes.
  • Isotopes of an element are chemically identical but physically different from each other.
  • They were discovered by Soddy.
Similarities and differences between isotopes of an element 
Classification of elements on the basis of number of isotopes:
Elements are classified as mono isotopic and poly isotopic as discussed below:
Mono isotopic elements:
The elements having only one isotope are called mono isotopic elements.
Example: Fluorine, iodine, arsenic, gold, sodium etc.
Poly isotopic elements:
The elements having two or more isotopes are called poly isotopic elements.
Examples:
  • Nitrogen has three isotopes. 
  • Hydrogen has three isotopes.
  • Carbon has three isotopes. 
  • Oxygen has three isotopes. 
  • Sulphur has four isotopes.
  • Nickel has five isotopes.
  • Calcium and palladium has six isotopes each.
  • Cadmium has nine isotopes.
  • Tin has eleven isotopes.
  • Silver has sixteen isotopes.

Comments

Post a Comment

Popular posts from this blog

Deoxyribonucleic acid (DNA)

Deoxyribonucleic acid (DNA) DNA is heredity material. It controls the properties and potential activities of a cell. Location in cell DNA occurs in chromosomes, in the nuclei of the cells and in much lesser amounts in mitochondria and chloroplast. Chemical composition of DNA DNA is made of four kinds of  nucleotides; d-adenosine monophosphate (d-AMP) d-guanosine monophosphate (d-GMP) d-cytidine monophosphate (d-CMP) d-thymidine monophosphate (d-TMP) These nucleotides are united with one another through phosphodiester linkages in a specific sequence to form long chains. Two nucleotides join to form  dinucleotide  e.g nicotinamide adenine dinucleotide  (NAD) which is important coenzyme in several oxidation-reduction reactions in the cell. Three nucleotides join to form  trinucleotide . Ratio of Bases in DNA In 1951,  Erwin Chargaff  provided data about the ratios of different bases present in DNA. This data suggested that ade...
Post a Comment
Read more

Mr chips important short questions.

Chapter#1 Question # 1:How does a person spend his time in old age after retirement? Answer : After retirement when a person becomes old, he has nothing to do. His time seems to pass like lazy cattle moving across a landscape(valley). Question # 2:Why did Chips keep on adjusting his timetable according to the school bells even after the retirement? Answer : After spending more than forty three(43) years at Brookfield, it was not possible for Chips to break his ties with school. He began to live across the road and Mrs. Wickets. That's why it was possible for Chips to keep on adjusting his timetable according to the school bells. Question # 3:How did Chips voice sound in old age? Answer : Although Chips had become old yet he did not loose the zeal and zeast for the life. So his voice remained resonant and lively even in his old age. Question # 4:What did Chips do before going to the bed? Answer : Chips was spending a pleasant and placid time at Mrs. Wickets after his retirem...
Post a Comment
Read more

Comparing MOLE OR AVOGADRO'S NUMBER

MOLE  The relative atomic mass of an element, the relative molecular mass of a molecule, the relative formula mass of an ionic substance or ionic mass of ionic specie when expressed in grams is called gram mole or simply mole. One mole of a substance is the amount in grams which contains 6.02×10 23  particles of that substance. It is denoted by “n”. It is abbreviated as “mol”. It is the  basic SI unit of measuring the quantity of substance. Example: (i)  Element                                Na       =          23g      = 1mole (ii) Molecular compound        H 2 O     =          18g      = 1mole (iii) Ionic compound         ...
Post a Comment
Read more