Reaction between copper(II) iodate and iodideWhich ion of iron is produced in a reaction between iron and copper(II) sulfate?Why should the redox reaction happen between the copper ions and iron atoms?Can the thermodynamic predictions of redox reactions based on E and dG contradict each other?Equation for reaction of tin(IV) and iodine to produce tin(IV) iodideWhat is the balanced equation for the reaction of potassium permanganate, iron sulfate, and sulfuric acid?Spontaneous reaction between chromium(III) and aluminumWhy does KMnO4 oxidize iodide to iodine in acidic medium, whereas iodide to iodate in alkaline medium?Stoichiometric reaction of hydrochloric acid, potassium nitrate, and copperCopper Mirror ReactionNo sign flipping while figuring out the emf of voltaic cell?
Tikz-cd diagram arrow passing under a node - not crossing it
Canada travel to US using Global Entry
Was Self-modifying-code possible just using BASIC?
If there's something that implicates the president why is there then a national security issue? (John Dowd)
YA book about blind creatures that live underground and take kid's eyes
Could a person damage a jet airliner - from the outside - with their bare hands?
Why is long-term living in Almost-Earth causing severe health problems?
How to get depth and other lengths of a font?
What are the unintended or dangerous consequences of allowing spells that target and damage creatures to also target and damage objects?
bash vs. zsh: What are the practical differences?
How can one's career as a reviewer be ended?
Can there be absolute velocity?
Oil draining out shortly after turbo hose detached/broke
Make Gimbap cutter
Why do radiation hardened IC packages often have long leads?
What STL algorithm can determine if exactly one item in a container satisfies a predicate?
Trying to get (more) accurate readings from thermistor (electronics, math, and code inside)
Why is the length of the Kelvin unit of temperature equal to that of the Celsius unit?
How durable are silver inlays on a blade?
What is Gilligan's full Name?
Is there a DSLR/mirorless camera with minimal options like a classic, simple SLR?
Is Dumbledore a human lie detector?
Seasonality after 1st differencing
Do you need to let the DM know when you are multiclassing?
Reaction between copper(II) iodate and iodide
Which ion of iron is produced in a reaction between iron and copper(II) sulfate?Why should the redox reaction happen between the copper ions and iron atoms?Can the thermodynamic predictions of redox reactions based on E and dG contradict each other?Equation for reaction of tin(IV) and iodine to produce tin(IV) iodideWhat is the balanced equation for the reaction of potassium permanganate, iron sulfate, and sulfuric acid?Spontaneous reaction between chromium(III) and aluminumWhy does KMnO4 oxidize iodide to iodine in acidic medium, whereas iodide to iodate in alkaline medium?Stoichiometric reaction of hydrochloric acid, potassium nitrate, and copperCopper Mirror ReactionNo sign flipping while figuring out the emf of voltaic cell?
$begingroup$
I was attempting the following question from IChO 1989, which involved balancing of redox equations. One may just expect this to be a typical iodate-iodide redox reaction, usually employed in iodometry. However, the presence of $ceCu(II)$ makes things a bit more complicated since it can also be reduced to give $ceCuI$.
To determine the solubility product of copper(II) iodate, $ceCu(IO3)2$, by iodometric titration in an acidic solution ($pu25 ^circ C$), $pu30.00 cm3$ of a $0.100$ molar sodium thiosulfate solution are needed to titrate $pu20.00 cm3$ of a saturated aqueous solution of $ceCu(IO3)2$.
1.1 Write the sequence of balanced equations for the above described reactions. [...]
After realising that $ce Cu^2+$ is reduced as well, I wrote the following overall equation :
$$ce2Cu^2+ + 2IO3^- + 12H^+ + 14I^- -> 7I2 + 2 CuI + 6H2O tag1$$
which is based on
$$beginalign
ce2Cu^2+ + 4I^- &-> 2CuI + I2 tag2 labeleq:cuii \
ce2IO3^- + 12H^+ + 10I^- &-> 6I2 + 6H2O tag3 labeleq:iodate
endalign$$
However, it turns out that the equation given in the answer scheme seems to have multiplied eq. $(refeq:iodate)$ by $2$ and the overall equation given is:
$$ce2Cu^2+ + 4IO3^- + 24H^+ + 24I^- -> 13I2 + 2CuI + 12H2O tag4$$
Usually, this is a trivial thing and does not matter. But in this case, it does since the reaction stiochiometry is completely different based on the equation given. Have I gone wrong somewhere?
redox stoichiometry
$endgroup$
add a comment |
$begingroup$
I was attempting the following question from IChO 1989, which involved balancing of redox equations. One may just expect this to be a typical iodate-iodide redox reaction, usually employed in iodometry. However, the presence of $ceCu(II)$ makes things a bit more complicated since it can also be reduced to give $ceCuI$.
To determine the solubility product of copper(II) iodate, $ceCu(IO3)2$, by iodometric titration in an acidic solution ($pu25 ^circ C$), $pu30.00 cm3$ of a $0.100$ molar sodium thiosulfate solution are needed to titrate $pu20.00 cm3$ of a saturated aqueous solution of $ceCu(IO3)2$.
1.1 Write the sequence of balanced equations for the above described reactions. [...]
After realising that $ce Cu^2+$ is reduced as well, I wrote the following overall equation :
$$ce2Cu^2+ + 2IO3^- + 12H^+ + 14I^- -> 7I2 + 2 CuI + 6H2O tag1$$
which is based on
$$beginalign
ce2Cu^2+ + 4I^- &-> 2CuI + I2 tag2 labeleq:cuii \
ce2IO3^- + 12H^+ + 10I^- &-> 6I2 + 6H2O tag3 labeleq:iodate
endalign$$
However, it turns out that the equation given in the answer scheme seems to have multiplied eq. $(refeq:iodate)$ by $2$ and the overall equation given is:
$$ce2Cu^2+ + 4IO3^- + 24H^+ + 24I^- -> 13I2 + 2CuI + 12H2O tag4$$
Usually, this is a trivial thing and does not matter. But in this case, it does since the reaction stiochiometry is completely different based on the equation given. Have I gone wrong somewhere?
redox stoichiometry
$endgroup$
$begingroup$
Well, I get what you got. Iodate to iodide is +6e balanced with protons and water. Cupric to cuprous is + 1e. A total of +7e for reduction. Two iodide to iodine is -2e oxidation. Multiply reduction by 2 and the oxidation by 7 and it works out. Can't speak for the "answer scheme".
$endgroup$
– user55119
May 27 at 1:51
$begingroup$
This question is clearly not closeable as homework because there is effort provided. If you want to close it, please describe your reasoning in a comment.
$endgroup$
– M.A.R. ಠ_ಠ
May 27 at 7:28
add a comment |
$begingroup$
I was attempting the following question from IChO 1989, which involved balancing of redox equations. One may just expect this to be a typical iodate-iodide redox reaction, usually employed in iodometry. However, the presence of $ceCu(II)$ makes things a bit more complicated since it can also be reduced to give $ceCuI$.
To determine the solubility product of copper(II) iodate, $ceCu(IO3)2$, by iodometric titration in an acidic solution ($pu25 ^circ C$), $pu30.00 cm3$ of a $0.100$ molar sodium thiosulfate solution are needed to titrate $pu20.00 cm3$ of a saturated aqueous solution of $ceCu(IO3)2$.
1.1 Write the sequence of balanced equations for the above described reactions. [...]
After realising that $ce Cu^2+$ is reduced as well, I wrote the following overall equation :
$$ce2Cu^2+ + 2IO3^- + 12H^+ + 14I^- -> 7I2 + 2 CuI + 6H2O tag1$$
which is based on
$$beginalign
ce2Cu^2+ + 4I^- &-> 2CuI + I2 tag2 labeleq:cuii \
ce2IO3^- + 12H^+ + 10I^- &-> 6I2 + 6H2O tag3 labeleq:iodate
endalign$$
However, it turns out that the equation given in the answer scheme seems to have multiplied eq. $(refeq:iodate)$ by $2$ and the overall equation given is:
$$ce2Cu^2+ + 4IO3^- + 24H^+ + 24I^- -> 13I2 + 2CuI + 12H2O tag4$$
Usually, this is a trivial thing and does not matter. But in this case, it does since the reaction stiochiometry is completely different based on the equation given. Have I gone wrong somewhere?
redox stoichiometry
$endgroup$
I was attempting the following question from IChO 1989, which involved balancing of redox equations. One may just expect this to be a typical iodate-iodide redox reaction, usually employed in iodometry. However, the presence of $ceCu(II)$ makes things a bit more complicated since it can also be reduced to give $ceCuI$.
To determine the solubility product of copper(II) iodate, $ceCu(IO3)2$, by iodometric titration in an acidic solution ($pu25 ^circ C$), $pu30.00 cm3$ of a $0.100$ molar sodium thiosulfate solution are needed to titrate $pu20.00 cm3$ of a saturated aqueous solution of $ceCu(IO3)2$.
1.1 Write the sequence of balanced equations for the above described reactions. [...]
After realising that $ce Cu^2+$ is reduced as well, I wrote the following overall equation :
$$ce2Cu^2+ + 2IO3^- + 12H^+ + 14I^- -> 7I2 + 2 CuI + 6H2O tag1$$
which is based on
$$beginalign
ce2Cu^2+ + 4I^- &-> 2CuI + I2 tag2 labeleq:cuii \
ce2IO3^- + 12H^+ + 10I^- &-> 6I2 + 6H2O tag3 labeleq:iodate
endalign$$
However, it turns out that the equation given in the answer scheme seems to have multiplied eq. $(refeq:iodate)$ by $2$ and the overall equation given is:
$$ce2Cu^2+ + 4IO3^- + 24H^+ + 24I^- -> 13I2 + 2CuI + 12H2O tag4$$
Usually, this is a trivial thing and does not matter. But in this case, it does since the reaction stiochiometry is completely different based on the equation given. Have I gone wrong somewhere?
redox stoichiometry
redox stoichiometry
edited May 27 at 12:19
orthocresol♦
41.7k7125256
41.7k7125256
asked May 27 at 0:55
Tan Yong BoonTan Yong Boon
4,45511551
4,45511551
$begingroup$
Well, I get what you got. Iodate to iodide is +6e balanced with protons and water. Cupric to cuprous is + 1e. A total of +7e for reduction. Two iodide to iodine is -2e oxidation. Multiply reduction by 2 and the oxidation by 7 and it works out. Can't speak for the "answer scheme".
$endgroup$
– user55119
May 27 at 1:51
$begingroup$
This question is clearly not closeable as homework because there is effort provided. If you want to close it, please describe your reasoning in a comment.
$endgroup$
– M.A.R. ಠ_ಠ
May 27 at 7:28
add a comment |
$begingroup$
Well, I get what you got. Iodate to iodide is +6e balanced with protons and water. Cupric to cuprous is + 1e. A total of +7e for reduction. Two iodide to iodine is -2e oxidation. Multiply reduction by 2 and the oxidation by 7 and it works out. Can't speak for the "answer scheme".
$endgroup$
– user55119
May 27 at 1:51
$begingroup$
This question is clearly not closeable as homework because there is effort provided. If you want to close it, please describe your reasoning in a comment.
$endgroup$
– M.A.R. ಠ_ಠ
May 27 at 7:28
$begingroup$
Well, I get what you got. Iodate to iodide is +6e balanced with protons and water. Cupric to cuprous is + 1e. A total of +7e for reduction. Two iodide to iodine is -2e oxidation. Multiply reduction by 2 and the oxidation by 7 and it works out. Can't speak for the "answer scheme".
$endgroup$
– user55119
May 27 at 1:51
$begingroup$
Well, I get what you got. Iodate to iodide is +6e balanced with protons and water. Cupric to cuprous is + 1e. A total of +7e for reduction. Two iodide to iodine is -2e oxidation. Multiply reduction by 2 and the oxidation by 7 and it works out. Can't speak for the "answer scheme".
$endgroup$
– user55119
May 27 at 1:51
$begingroup$
This question is clearly not closeable as homework because there is effort provided. If you want to close it, please describe your reasoning in a comment.
$endgroup$
– M.A.R. ಠ_ಠ
May 27 at 7:28
$begingroup$
This question is clearly not closeable as homework because there is effort provided. If you want to close it, please describe your reasoning in a comment.
$endgroup$
– M.A.R. ಠ_ಠ
May 27 at 7:28
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
In your eq. (4), the copper/iodate ratio was adjusted to match the stoichiometry present in copper(II) iodate. 1 copper(II) ion to 2 iodate ions equals 2 copper(II) ions to 4 iodate ions.
$endgroup$
add a comment |
Your Answer
StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "431"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);
else
createEditor();
);
function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);
);
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fchemistry.stackexchange.com%2fquestions%2f115979%2freaction-between-copperii-iodate-and-iodide%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
In your eq. (4), the copper/iodate ratio was adjusted to match the stoichiometry present in copper(II) iodate. 1 copper(II) ion to 2 iodate ions equals 2 copper(II) ions to 4 iodate ions.
$endgroup$
add a comment |
$begingroup$
In your eq. (4), the copper/iodate ratio was adjusted to match the stoichiometry present in copper(II) iodate. 1 copper(II) ion to 2 iodate ions equals 2 copper(II) ions to 4 iodate ions.
$endgroup$
add a comment |
$begingroup$
In your eq. (4), the copper/iodate ratio was adjusted to match the stoichiometry present in copper(II) iodate. 1 copper(II) ion to 2 iodate ions equals 2 copper(II) ions to 4 iodate ions.
$endgroup$
In your eq. (4), the copper/iodate ratio was adjusted to match the stoichiometry present in copper(II) iodate. 1 copper(II) ion to 2 iodate ions equals 2 copper(II) ions to 4 iodate ions.
edited May 27 at 12:16
orthocresol♦
41.7k7125256
41.7k7125256
answered May 27 at 1:00
Oscar LanziOscar Lanzi
17.1k22853
17.1k22853
add a comment |
add a comment |
Thanks for contributing an answer to Chemistry Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fchemistry.stackexchange.com%2fquestions%2f115979%2freaction-between-copperii-iodate-and-iodide%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
$begingroup$
Well, I get what you got. Iodate to iodide is +6e balanced with protons and water. Cupric to cuprous is + 1e. A total of +7e for reduction. Two iodide to iodine is -2e oxidation. Multiply reduction by 2 and the oxidation by 7 and it works out. Can't speak for the "answer scheme".
$endgroup$
– user55119
May 27 at 1:51
$begingroup$
This question is clearly not closeable as homework because there is effort provided. If you want to close it, please describe your reasoning in a comment.
$endgroup$
– M.A.R. ಠ_ಠ
May 27 at 7:28