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Author Question: A certain radioactive element has a half-life of one hour. If you start with a 1-g sample of the ... (Read 128 times)

jace

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A certain radioactive element has a half-life of one hour. If you start with a 1-g sample of the element at noon, how much of this same element will be left at 3:00 PM?
 
  A) 0.5 gram
  B) 0.25 gram
  C) 0.125 gram
  D) 0.0625 gram

Question 2

A sample of iron weighs more after it rusts because ________.
 
  A) it has expanded into a greater volume
  B) rust contains twice as many iron atoms
  C) of the additional oxygen it contains
  D) Wrong. Iron actually weighs less after it rusts



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Kdiggy

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Answer to Question 1

C

Answer to Question 2

C



jace

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Both answers were spot on, thank you once again



Kdiggy

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