Gen Chem

posted by .

Chromium can be electroplated from an aqueous solution containing sulfuric acid and chromic acid, H2CrO4. What current is required to deposit chromium at a rate of 1.25 g/min?

1mol H2CrO4 has 51.996 grams

current= coulomb/sec

How do I convert to get coulombs from the problem?

  • Gen Chem -

    You know 96,485 Coulombs is required to plate out 51.996/6 g Cr (Cr goes from +6 in H2CrO4 to zero in Cr) = 8.666 g Cr.
    You want to plate 1.25 g/min which is 1.25/60 = 0.02083 g/sec.

    96,485 C x 0.02083/8.666 = ??Coulombs.
    1 ampere current = 1C/sec
    so you will need ?? C/sec or that much current.
    Check my thinking. Check my numbers.

  • Gen Chem -

    That makes sense, just so I understand, how did you get 8.666 g Cr? What does the +6 to 0 mean?

  • Gen Chem -

    Re-read my first response. Cr goes from +6 in H2CrO4 to zero in Cr metal. That's a change of 6 electrons. The equivalent weight of a material is molar mass/delta electrons = 51.996 (I took your number and didn't check it out) or 51.996/6 = 8.666 g as the equivalent weight of Cr in this reaction.

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

    Chromium metal can be plated onto an object from an acidic solution of dichromate ions. What average current is required to plate 17.8 g of chromium metal in a time of 2.20 h?
  3. chemistry

    A car bumper is plated with chromium using chromium(III) ions in solution. If a current of 54 A flows in the cell for 45 min 30 s, determine the mass of chronium deposited on the bumper.
  4. chemistry

    A 7.500-mg sample of chromium-55 is analyzed after 14.0 min. and found to contain 0.469 mg of chromium-55. what is the half-life of chromium-55?
  5. Chemistry

    How much time is required to electroplate 6.530 µg of chromium from a potassium dichromate solution, by using a current of 118 mA?
  6. Gen Chem 1

    A tanker truck carrying 2.01×10^3kg of concentrated sulfuric acid solution tips over and spills its load. The sulfuic acid is 95.0% H2SO4 by mass and has a density of 1.84g/L. Sodium Carbonate (Na2CO3)is used to neutralize the the …
  7. chemistry

    a 7.500-mg sample of chromium-55 is analyzed after 14.0 min and found to contain 0.469 mg of chromium-55. what is the half-life of chromium-55
  8. chemistry

    How many grams of phosphoric acid can be made from 200 g of dichromate and 150 grams of hypophosphorous acid?
  9. chemistry

    Plastic articles can be chromium-plated by coating them with thin layer of graphite paste,placing them in a bath of aqueous chromium(III) sulphate and electroplating. a)Suggest a reason why the article is first coated with graphite. …
  10. Chem

    How many grams of Ni would be electroplated if a constant current of 7.2 amperes is passed through a solution of NiSO4 for 90.0 min?

More Similar Questions