« previous next »

Author Question: The two elements silicon and oxygen, taken together, make up about what percent of Earth's crust by ... (Read 88 times)

tatyanajohnson

  • Hero Member
  • *****
  • Posts: 569
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

  • Sr. Member
  • ****
  • Posts: 342
Reply #1 on: Jul 28, 2018
Answer to Question 1

d

Answer to Question 2

b


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question

tatyanajohnson

  • Hero Member
  • *****
  • Posts: 569
Reply #2 on: Jul 28, 2018
Thank you!


isabelt_18

  • Sr. Member
  • ****
  • Posts: 342
Reply #3 on: Jul 28, 2018
Always glad to help...


« previous next »
 

Did you know?

Dogs have been used in studies to detect various cancers in human subjects. They have been trained to sniff breath samples from humans that were collected by having them breathe into special tubes. These people included 55 lung cancer patients, 31 breast cancer patients, and 83 cancer-free patients. The dogs detected 54 of the 55 lung cancer patients as having cancer, detected 28 of the 31 breast cancer patients, and gave only three false-positive results (detecting cancer in people who didn't have it).

Did you know?

A serious new warning has been established for pregnant women against taking ACE inhibitors during pregnancy. In the study, the risk of major birth defects in children whose mothers took ACE inhibitors during the first trimester was nearly three times higher than in children whose mothers didn't take ACE inhibitors. Physicians can prescribe alternative medications for pregnant women who have symptoms of high blood pressure.

Did you know?

Eat fiber! A diet high in fiber can help lower cholesterol levels by as much as 10%.

Did you know?

Hyperthyroidism leads to an increased rate of metabolism and affects about 1% of women but only 0.1% of men. For most people, this increased metabolic rate causes the thyroid gland to become enlarged (known as a goiter).

Did you know?

You should not take more than 1,000 mg of vitamin E per day. Doses above this amount increase the risk of bleeding problems that can lead to a stroke.

Scaling the Earth down to the size of a basketball, the Moon is roughly the size of a tennis ball. T Scaling the Earth down to the size of a basketball, the Moon is roughly the size of a tennis ball. T
Cutaway Model of Earth Cutaway Model of Earth
Solar EM Radiation Penetration into Earth's Atmosphere Solar EM Radiation Penetration into Earth's Atmosphere
Earth’s Spheres Earth’s Spheres
Earth emits radiation back out to space from all surfaces, both day and night Earth emits radiation back out to space from all surfaces, both day and night
Severe arthritis can make everyday activities, like writing, typing, and handling objects Severe arthritis can make everyday activities, like writing, typing, and handling objects
Video: Primary and secondary response to infection

For a complete list of videos, visit our video library