Chemistry

posted by .

What is the oxidation number of chromium in K2Cr2O7?

I know that K = 1
O=-2 so 7*-2=-14

I do not know what to do now. Thank you for your help!

  • Chemistry -

    That's good, you have a good foundation. Since you're only looking for the oxidation number of chromium at this point, let's look at it like this. The polyatomic ion Cr2O7, or dichromate, has a 2- charge. Hence, the charges of the individual ions have to add up to -2. So, we set up an equation, where x is the oxidation number of chromium. In this case, we'll have 2(x) + 7(-2) = -2. See what I did there? I set up an equation so that the individual charges will all add up to -2, so let's solve for x, and when you do that, you'll get +6, which happens to be the answer!

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    Chromium is electroplated from an aqueous solution containing H2SO4 and H2CrO4. What current is required to deposit chromium at rate of 1.25g/min. 1.25g x 1mol/51.9961 = .0240mol Now I just don't know how to figure out the number of …
  2. chemistry

    The oxidation number of chromium (Cr) in the dichromate ion (Cr2O72-) is A. +2 B. +4 C. +6 D. +7 E. -2
  3. chemistry

    Find the number of K atoms, C atoms, and O atoms in 95.5g of K2Cr2O7. (Potassium 2, Chromium 2, Oxygen 7).
  4. Chemistry

    Since the oxidation number of Chromium is +3, and the oxidation number of Silicon is -4. Why is the chemical formula for Chromium III Silicide Cr3Si2?
  5. Chemistry(Please check)

    What is the oxidation number of chromium in K2Cr2O7 so k=+1 (2) = 2 O=-2(7) = -14 2x + 1 +(-14) = 0 2x-12=0 x=6 so Cr is 6 Is this correct?
  6. chemistry

    Which statement best describes the oxidation numbers of the atoms found in magnesium chloride?
  7. Chemistry

    Hello there! I was wondering if you could check my answers for me?
  8. CHEMISTRY

    Hello there! I was wondering if you could check my answers for me?
  9. Chemistry

    Which atom has a change in oxidation number of –3 in the following redox reaction?
  10. chemistry

    Write the oxidation and reduction half-reactions for a silver-chromium voltaic cell. Identify the anode, cathode, and the direction of electron flow. Ag+ + e-  Ag Cr  Cr2+ + 2e- or Cr  Cr3+ + 3e- ?

More Similar Questions