Chem. reply+asap!

In some industrial processes, sodium chromate is added to water coolants.
When the coolant is drained, the chromate ions can be removed through an
electrolysis process that uses an iron anode. The products of the electrolysis
are aqueous iron(II) ions and solid chromium(III) hydroxide, a recoverable
pollutant. The half-reaction involving the chromate ion is

CrO42–(aq) + 4 H2O (l) + 3 e –>>>Cr(OH)3(s) + 5 OH –(aq)

a) I figured out, thanks!

b) A current of 3.00 A is applied for 48.0 h to a cell containing a 400 g iron
anode. What is the final mass of the iron anode?
My work:
ItA/QV=m
(3)(172800)(55.85)/(9.65x10^4)(6)=50g
My new answer is 50grams. Is this right?

c) Suggest an alternative anode material that would last longer than iron. Support
your answer with relevant calculations and explanations.
My answer:
For this I got that aluminum was the answer because it had a greater electrons in half-reaction. (3V). First, is this right, and second how would I show it by calculation?

Thanks sooo much!


b) A current of 3.00 A is applied for 48.0 h to a cell containing a 400 g iron
anode. What is the final mass of the iron anode?
My work:
ItA/QV=m
(3)(172800)(55.85)/(9.65x10^4)(6)=50g
My new answer is 50grams. Is this right?
This looks ok except that isn't the 6e you used for 3 mols Fe to go into solution. (Alternatively, the half reaction showed 2e.) Second, is the 50 g what is left or what went into solution and the final mass of the iron electrode would then be 400 - 50 g (of course the 50 g will change to 150g if you decide you should use 2e instead of 6e). Check me out on this??

c) Suggest an alternative anode material that would last longer than iron. Support
your answer with relevant calculations and explanations.
My answer:
For this I got that aluminum was the answer because it had a greater electrons in half-reaction. (3V).
First, is this right, and second how would I show it by calculation?

I'm not exactly sure what is meant by this question but your answer sounds ok. You can run the same calculation by starting with 400 g Al (instead of Fe) and going through the exact calculation you did for Fe but substitute 3e for the change in electrons and substitute 27 for the molar mass instead of the 55.85. Make the calculation and see how things turn out. Remember to subtract the final anwer you obtain from 400 to find how much is left.Again, check me out on this.

  1. 👍 0
  2. 👎 0
  3. 👁 62
asked by yo!

Respond to this Question

First Name

Your Response

Similar Questions

  1. chemistry

    Hey...how r u guys..thanks for helping me on my previous questions...can u help me solve two questions and check one? Thanks, all the questions are related to the info given: In some industrial processes, sodium chromate is added

    asked by David on June 18, 2006

  2. Chemistry

    A 50/50 blend of engine coolant and water (by volume) is usually used in an automobile\'s engine cooling system. If your car\'s cooling system holds 4.90 gallons, what is the boiling point of the solution? Make the following

    asked by Heather on February 21, 2012

  3. Chemistry

    When aqueous solutions of lead(II) ion are treated with potassium chromate solution, a bright yellow precipitate of lead(II) chromate, PbCrO4, forms. How many grams of lead chromate form when a 1.60-g sample of Pb(NO3)2 is added

    asked by Jamie lee on April 27, 2015

  4. chemistry

    A 50/50 blend of engine coolant and water (by volume) is usually used in an automobile\'s engine cooling system. If your car\'s cooling system holds 4.20 gallons, what is the boiling point of the solution? Make the following

    asked by Morgan Parker on March 2, 2013

  5. Chem 2

    A 50/50 blend of engine coolant and water (by volume) is usually used in an automobile\'s engine cooling system. If your car\'s cooling system holds 4.00 gallons, what is the boiling point of the solution? Make the following

    asked by Paulie on July 14, 2012

  6. math

    The radiator in a car is filled with a solution of 70 per cent antifreeze and 30 per cent water. The manufacturer of the antifreeze suggests that for summer driving, optimal cooling of the engine is obtained with only 50 per cent

    asked by jp on January 26, 2015

  7. Algebra

    The radiator in a car is filled with a solution of 75 per cent antifreeze and 25 per cent water. The manufacturer of the antifreeze suggests that for summer driving, optimal cooling of the engine is obtained with only 50 per cent

    asked by Sue on March 10, 2015

  8. math

    The radiator in a car is filled with a solution of 70 per cent antifreeze and 30 per cent water. The manufacturer of the antifreeze suggests that for summer driving, optimal cooling of the engine is obtained with only 50 per cent

    asked by jp on January 27, 2015

  9. Math algebra

    The radiator in a car is filled with a solution of 60% antifreeze and 40% water. The manufacturer of the the antifreeze suggests that, for summer diving, optimal cooling of the engine is obtained with only 50% antifreeze. If the

    asked by Shane on November 24, 2015

  10. Chemistry

    Hi, I have a few chemistry problems that I'm having trouble solving. I put my attempted solutions after the problems in *'s. There was one problem I had no idea how to solve. What concentration of silver chromate (Ksp = 9.0 x

    asked by Maggie on April 12, 2010

More Similar Questions