Magnesium Has 3 Stable Isotopes with Masses of 23

question 68

Multiple Choice

Magnesium has 3 stable isotopes with masses of 23.98504, 24.98584, and 25.98259 respectively. Mg-25 is 10.13%. What are the percentages of the other two isotopes?

• A) 78.9% and 10.9%
• B) 50% and 50%
• C) 44.9% and 44.9%
• D) 83.6% and 16.4%
• E) 78.9% and 21.1%

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