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Last week we performed an experiment in chemistry class engaging Redox reactions (for those who are not familiar with the term i will explain shortly but there is also an explanation in Wikipedia).

Redox reactions are reduction and oxidation, the basic is that materials changing electrons between them and by doing so new materials are created.

Anyway the subject of the experiment was cleaning silver and I thought it would be useful and also interesting.

Step 1: Materials

For this project we will need:

- A kettle.

- A bowl.

- Aluminium foil.

- Baking soda.

- Silver cutlery and jewelries.

Step 2: The Cleaning Proccess

The cleaning is done by the next steps:

Put water to boil.

Wrap the inside of the bowl with foil.

Insert everything made of silver you want to clean.

Pour enough hot water to cover everything.

Pour about two teaspoons of baking soda.

During the process you might notice bubbles and a scent similar to eggs or sulfur and that's the sign it works.

Step 3: Conclusion

As you can see in the first photo above the process partly worked and our silver stuff is only a bit cleaner.

There are two possible explanations:

-The metal you tried to clean was not silver or was partly silver.

-The process is needed to be repeated.

And as you can see in the second and third photos the cups are much cleaner now and that is because I have repeated the process once again. The advantage of this method is that it restores the "dirty" silver and does not remove it.

Step 4: Chemical Equitation and Explanation

Well.. in this project we see another use of Red-Ox reactions but lighting fire.

The blackened Silver phenomenon is caused by a pollutant in the air called Hydrogen sulfide (H2S) and that leads us to our first equitation:4 Ag(s) + 2 H2S(g) + O2(g) → 2 Ag2S(s) + 2 H2O(l)

This is a Red-Ox reaction between the silver to H2S, the silver turns into Ag2S and that is the "dirt" we see on the silver.

Now, in order to clean the silver we need to turn the Ag2S into Ag back again, In order to do this we will use a better reducer metal (Reducer is the substance in the reaction that gives electrons) than silver, like Aluminium, that will be oxidized, just as the silver was. The equitation here is:

2 Al(s) + 3 Ag2S(s) + 6 H2O(l) → 6 Ag(s) + 2 Al(OH)3 (s) + 3 H2S (g)

As we can see the Al starts as a solid and turns into Al(OH)3 and the silver, which started as Ag2S turns into Ag.

The scent of sulfur that is noticed during the process is the H2S's smell.

Now a question rises: why did we use Baking soda???

So Baking soda has two roles here:

Firstly, it is a cleaning substance for silver.

Secondly, the soda is a base unlike Hydrogen sulfide which is acid. The Baking soda neutralizes the acid and prevents it from hurting the silver. This happens in the reaction:

H2S (aq) + NaHCO3 (aq) -> NaHS (aq) + CO2 (g) + H2O (l)

After this reaction we're left with water, Carbon dioxide and Sodium hydrosulfide that won't harm silver.

Step 5: All for Now

Hope you enjoyed this guide, more experiments with Red-Ox reactions coming soon so be sure to check my profile, my Facebook page and my YouTube Channel.

Any comments and questions about the process and Red-Ox will accepted happily.

Don't forget to vote :P

Love the instruction and explanation :) this worked better than anything I've previously tried!
Happy to hear tnx for the comment :)
<p>Thank you so much for your great information. This is very useful for us</p>
your welcome, glad you enjoyed :)
<p>I love how you didn't only make it an instruction but also added the scientific explanation!</p>
Thanks and of course. I believe that if you attempt an experiment, knowing how it works and what is the explanation for it adds a lot for your motivation and curiosity ;-)
<p>Definitely. It's also quite nice to see something I've been learning about in chemistry class the past month used in real life : ) </p>
Redox has many uses like in my guide of how to start fire . Have you performed any experiments in class?
<p>We've had 3 demo experiments: </p><p>- the rusting of iron (which is still ongoing)<br>- sodium in water <br>- 5 cent in concentrated nitric acid </p><p>I believe we still have to do one experiment ourselves, which is an observation of different redox reactions (potassium permanganate with sodium and other combinations)</p>
<p>Sounds cool, how do you rust the iron? We also had a few in class. Potassium Permanganate is a very cool material, try suggesting to your teacher to do the experiment in which you start fire with it and glycerin (see how <a href="https://www.instructables.com/id/FIRE-Chemical-combustion/" rel="nofollow">here</a>), another cool one is creating a thunder storm in a test tube with KMnO4, Ethanol and H2SO4, try asking your teacher if she is familiar with these. Tell me if she did. I believe that these would impress your class.</p>
<p>It worked great :)Thank you very much for sharing this :)</p>
Wow I'm very glad it did work:-) and thank you for commenting. More cool science stuff coming soon
Rub cigarette ash on silver or white gold jewellery and wash it off.
This method looks easy than using scrub and lot of energy...I will try this ☺ Thanks for sharing the great ideas ?
You're welcome :-) by the way using scrub will remove silver while this method will restore it :p
<p>This looks so cool and the results speak for themselves!</p>
Thanks tomatoskins. Cool name by the way

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