« previous next »

Author Question: In drawing the Lewis structure for the dichromate ion, how many valence electrons does chromium have? (Read 1140 times)

sammy

  • Hero Member
  • *****
  • Posts: 818
on: Sep 20, 2013
The periodic table says that Cr has only 1 valence electron but other sources say that when drawing a Lewis structure, it is considered to have 6 valence electrons. Why?


erika

  • Hero Member
  • *****
  • Posts: 522
Reply #1 on: Sep 20, 2013
6 is correct. Cr2O7(-2) gives you 7 oxygens = -14 + (-2) = 12 divided by two Cr per anion = 6 for the formal valence of Cr in dichromate.


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question

theo

  • Hero Member
  • *****
  • Posts: 698
Reply #2 on: Sep 20, 2013
The six valence electrons of chromium are the 4s2 and the 3d4. In this way, the chemistry of chromium is analogous to that of sulfur, 3s2 3p4.


sammy

  • Hero Member
  • *****
  • Posts: 818
Reply #3 on: Sep 27, 2013
Marking this topic solved :D

Thanks so much for the help


« previous next »
 

Did you know?

In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.

Did you know?

Malaria was not eliminated in the United States until 1951. The term eliminated means that no new cases arise in a country for 3 years.

Did you know?

Certain chemicals, after ingestion, can be converted by the body into cyanide. Most of these chemicals have been removed from the market, but some old nail polish remover, solvents, and plastics manufacturing solutions can contain these substances.

Did you know?

Patients should never assume they are being given the appropriate drugs. They should make sure they know which drugs are being prescribed, and always double-check that the drugs received match the prescription.

Did you know?

Drug abusers experience the following scenario: The pleasure given by their drug (or drugs) of choice is so strong that it is difficult to eradicate even after years of staying away from the substances involved. Certain triggers may cause a drug abuser to relapse. Research shows that long-term drug abuse results in significant changes in brain function that persist long after an individual stops using drugs. It is most important to realize that the same is true of not just illegal substances but alcohol and tobacco as well.

Female reproductive structure and function in humans. Female reproductive structure and function in humans.
General structure of a virus. General structure of a virus.
Structure of HIV. Structure of HIV.
The structure of a lipotechoic acid The structure of a lipotechoic acid
Structure of a clathrin-coated pit Structure of a clathrin-coated pit
Reconstruction Drawing of the Giza Plateau Seen from Above Reconstruction Drawing of the Giza Plateau Seen from Above
Video: Spermatogenesis Animation

For a complete list of videos, visit our video library