A 60-gram sample of radioactive isotope is measured after two half-lives have passed. What pair of percentages describe the sample after two-half lives? A.) 50% unchanged and 50% stable B.) 25% unchanged and 75% stable C.) 12.5% unchanged and 87.5% stable D.) 75% unchanged and 25% stable
Answers
Answer: B.) 25% unchanged and 75% stable
Explanation:
Now, to calculate the initial amount of radioactive isotope
where,
a = amount of reactant left after n-half lives = 60 g
= Initial amount of the reactant = ?
n = number of half lives= 2
Putting values in above equation, we get:
Thus percentage of sample unchanged=
The percentage of sample decayed or has become stable=
Answer:
B. 25% unchanged and 75% stable
Explanation:
Edge 2021
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2 images attatched below
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B) boiling point, volume
C) flammability, volume
D) melting point, reactivity with water
Plz answer this question quickly, it’s really important
Answers
I believe the correct answer is D. melting point, reactivity with water.