1. Questions

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. 👍
  2. 👎
  3. 👁
yo!

Respond to this Question

First Name

Your Response

Similar Questions

  1. chemistry

    The Ksp of Ag2CrO4(s) is 1.12 x 10^-12. Calculate the molar solubility of AgCrO4(s) a)in pure water b) in a solution of 0.10 mol/L sodium chromate, Na2CrO4(s)

  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 4.20 gallons, what is the boiling point of the solution? Make the following

  3. Chemistry

    1.What is the pH of a solution containing 0.042 M NaH2PO4 and 0.058 M Na2HPO4 ? The pKa of sodium phosphate is 6.86. pH = 6.86 + log [0.058] / [0.042]; pH = 6.86 + 0.14; pH = 7.00 That is my answer to the above question. The

  4. Chemistry

    Silver chromate is sparingly soluble in aqueous solutions. The Ksp of Ag2CrO4 is 1.12× 10–12. What is the solubility (in mol/L) of silver chromate in 1.4 M potassium chromate aqueous solution? In 1.4 M silver nitrate aqueous

  1. Chemistry

    Write a balanced equation for the following: aqueous barium chloride reacts with aqueous sodium chromate to form aqueous sodium chloride plus solid barium chromate.

  2. chemistry

    Sodium metal and water reacts to form hydrogen and sodium hydroxide. If 5.98g of sodium react with water to form .26g of hydrogen and 10.40g of sodium hydroxide, what mass of water was consumed in the reaction?

  3. Chemistry

    When sodium chloride, NaCl, is added to water, it forms a solution. Rank the steps involved in the dissolution of salt in water from first step to last step. To rank items as equivalent, overlap them. a.) NaCl crystal is added to

  4. Chemistry Balancing Equations

    Can you please tell me if these are correct? 1. Sodium Hydrogen Sulfite reacts with hydrochloric acid to produce sulfur dioxide gas, water and sodium chloride NaHSO3 + HCl -----> SO2 + H2O + NaCl 2. Sodium nitrate reacts with

  1. Science

    1. Which accounts for the highest water withdrawals in the United States? A.mining B. industrial uses C. irrigation D. thermoelectric power 2.Which is the most prevalent source of agricultural water pollution? A. pesticides B.

  2. 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

  3. Chemistry

    In a mountainous location, the boiling point of pure water is found to be 95 degrees Celsius. How many grams of sodium chloride much be added to 1 kg of water to bring the boiling point back to 100 degrees Celsius? Assume that

  4. Chemistry

    solid sodium reacts violently with water producing heat, hydrogen gas and sodium hydroxide. How many molecules of hydrogen gas are produced when 65.4g of sodium are added to water? 2Na(s)+ 2H2O(l) -->. 2NaOH(aq) + H2(g). Can

You can view more similar questions or ask a new question.