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Author Question: One mole of Strontium-90 is decaying with a half life of 28. years. After 61. years, how much ... (Read 51 times)

washai

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on: Jul 29, 2018
One mole of Strontium-90 is decaying with a half life of 28. years. After 61. years, how much Strontium is left and what is its activity?
 
  What will be an ideal response?

Question 2

A very fine sample is placed 0.15 cm from the objective of a microscope. The focal length of the objective is 0.14 cm and of the eyepiece is 1.0 cm. The near-point distance of the person using the microscope is 25.0 cm.
 
  What is the final magnification of the microscope? A) -375
  B) -242
  C) -108
  D) -142
  E) -100


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Koolkid240

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Reply #1 on: Jul 29, 2018
Answer to Question 1

0.22 mole; 5.5  10-3 mole/yr = 1.0  1014 Becquerel = 2.8  103 Curie

Answer to Question 2

A


washai

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Reply 2 on: Jul 29, 2018
Excellent

smrtceo

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Reply 3 on: Yesterday
Gracias!

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