Question

<br />29. Iron in nature exists in three isotopic forms :<br />Fe54, Fe56, Fe57. The percentage abundance<br />of Fe54 and Fe57 are equal and the average<br />atomic mass of Fe is 55.95 then percentage<br />abundance of Fe56 is<br />(1) 80%<br />(2) 85%<br />(3) 90%<br />(4) 95%<br /><br />​

Answer 1

Answer:

3. 90%

Explanation in the pic attached.

Main thing is to know the formula correcting otherwise only calculations.

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