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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 127 times)

jace

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on: Aug 27, 2018
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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Reply #1 on: Aug 27, 2018
Answer to Question 1

C

Answer to Question 2

C


jace

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Reply #2 on: Aug 27, 2018
Both answers were spot on, thank you once again


Kdiggy

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Reply #3 on: Aug 27, 2018
Great! Please up vote :D


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