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Author Question: The two elements silicon and oxygen, taken together, make up about what percent of Earth's crust by ... (Read 90 times)

tatyanajohnson

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on: Jul 28, 2018
The two elements silicon and oxygen, taken together, make up about what percent of Earth's crust by mass?
 a. 25
  b. 64
  c. 50
  d. 75

Question 2

If atoms unite by transfer of electrons, they form
 a. an organic compound.
  b. an ionic compound.
  c. a polar molecule.
  d. a covalent compound.


isabelt_18

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Reply #1 on: Jul 28, 2018
Answer to Question 1

d

Answer to Question 2

b


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tatyanajohnson

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Reply #2 on: Jul 28, 2018
Thank you!


isabelt_18

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Reply #3 on: Jul 28, 2018
Always glad to help...


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