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प्रश्न
The average atomic mass of a sample of an element X is 16.2 u. What are the percentages of isotopes `""_8^16X" and """_8^18X` in the sample?
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उत्तर
It is given that the average atomic mass of the sample of element X is 16.2 u.
Therefore,
The atomic mass of the given element X is = 16.2 u.
Let `""_8^16 X` percentage = a
Then `""_8^18X` percentage = (100 − a)
Average mass of X = `16("a"/100) + 18((100 - "a")/100)`
16.2 = `((16"a")/100) + ((1800 - 18"a")/100)`
1620 = 1800 − 2a
1800 - 1620 = 2a
180 = 2a
a = `180/2`
a = 90
Therefore `""_8^16X"` percentage = 90%
And `""_8^18X"` percentage = 100 − 90
= 10%
संबंधित प्रश्न
MATCH THE COLUMNAS
| 1. Jpham Dalton | a. Neutrons |
| 2. Atom | b. Model of the atom |
| 3. Chadwick | c.The atomic theory of matter |
| 4. Rutherfrod | d. Positively charged |
| 5. Protons | e. Electricity neutral |
| 6. Nuclear fusion | f. Generator of electricity |
| 7.Gamma -rays | g. High penetrating power |
| h.Energy in sun |
TRUE \ FALSE
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