Question

atom at element having same atomic no. but different mass are known as _________.​

Answer 1

Answer:

they are called isotopes

Answer 2

Answer:

isotopes are referred as those elements which having same atomic number but different atomic mass . the main reason of occurring isotopes is due the presence of different number of neutrons in an element having the same atomic number as mass number is the sum of the number of neutrons and protons . example of isotopes are carbon - 13 , carbon -14 and carbon -15 are the three isotopes of carbon with mass number 12 , 13 and 14 .

so , isotopes is your answer

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