A chemical change happens when one substance transforms into a different substance. A good example is when bare wood burns and turns into charcoal or when an iron nail turns to rust. If you’ve ever had a silver piece that suddenly changed color, you may be wondering if it had undergone a chemical change.
The opposite of a chemical change is a physical change. In most cases, it is possible to under a physical change such as freezing of water. However, this might not always be the case with a chemical change. Interestingly, in the case of silver tarnishing, it is possible to clean tarnished silver. In this article, we will take a closer look at what causes silver to tarnish, how you can clean your tarnished silver jewelry, and what you can do to prevent it from happening in the future.
Is silver tarnishing a chemical change?
Yes, silver tarnishing is a chemical change. When a silver piece is exposed to moisture or sulphur-containing gases in the atmosphere, this causes the silver to blacken or become discolored. This is called tarnishing.
What is silver tarnishing?
Tarnish is the product of the oxidation of silver and sulfur-containing substances to their sulfides and oxides. This occurs when other metals mixed with silver are exposed and react to moisture and sulphur compounds in the atmosphere.
When silver tarnishes, it turns dark and if it continues long enough, it could turn black. Although, pure silver does not tarnish. So, if a piece of silver jewelry or silverware tarnishes, it is not the silver itself that reacts or darkens but the metal alloy in it.
The silver darkens when silver reacts chemically with sulfur-containing substances in the atmosphere and forms silver sulphide. The silver sulphide, which is black, forms a thin coating on the surface of the silver. This darkens the silver and causes the silver to tarnish.
Is it normal for silver to tarnish?
Pure silver is resistant to tarnish but silver is usually mixed with other metals because it is too soft to be used in its pure form to make jewelry. So, it is absolutely normal for silver to tarnish. Every silver jewelry tarnishes over time.
Basically, all silver jewelry are alloyed with metals. These metals will naturally react with the environment or atmosphere. Pure silver will not normally react with the atmosphere but as stated earlier, silver in its pure state is way too soft to be used alone.
Hence, the silver has to be alloyed with metals which will react with the atmosphere with time and cause the silver to blacken.
So, if you go through your jewelry box and discover that some of your favorite silver jewelry look yellowish or blackish, do not panic. It is absolutely normal and it can be reversed.
Why is silver tarnishing a chemical change?
The tarnishing of silver results in the formation of a new substance called silver sulphide, which has different properties from the original silver. The reaction is as follows; silver metal reacts chemically with sulphur-containing compounds to form silver sulphide:
4Ag(s) + 2H2S(g) + O2(g) --> 2Ag2S(s) + 2H2O(l)
To put it simply, silver tarnishing is a chemical change because it is caused by a chemical reaction and it leads to a color change.
Why silver gets tarnished?
Silver tarnishes because of oxidation. When silver gets in contact with sulphur-containing gases or moisture in the atmosphere, it is bound to tarnish. Silver tarnishing is inevitable. Although, there are certain things that speed up the process.
Moisture
When your silver piece is wet or moist, it can speed up the process of tarnishing. If your silver piece is wet, do not air-dry, instead, dry it with a piece of fabric because air-drying silver can lead to spots. Also, whenever you go swimming, remember to take off your silver jewelry.
Exposure to sulphur-containing substances
When a silver piece is exposed to sulphur-containing substances like latex, paper, wool, and rubber, it speeds up the rate of tarnishing.
Exposure to oxidants
When silver is exposed to certain oxidants such as bleach, it is bound to tarnish faster. So, if you’re washing or bleaching your clothes or anything, you are advised to take off your silver jewelry.
Exposure to certain food substances
Some food substances such as eggs, onions, spinach, and garlic can accelerate silver tarnishing. So, it is important for you to keep your silver piece far away from these foods and if it comes in contact with any of these foods by any chance, make sure to clean it immediately. Remember that moisture is a no-no. So don’t use water to clean it.
Does tarnish harm silver?
Tarnish only affects the surface of the silver piece. It does not affect the metal content of the piece. The tarnish only damages the surface and can be cleaned. Silver tarnish is not permanent, so I wouldn’t say it harms or damages silver.
Although, if a silver piece is tarnished, not cleaned properly, or cleaned excessively, it can affect the value of the silver piece. So, if you want the value of your silver piece retained, you must store it properly and clean it properly but not excessively. So, while you want to keep your silver piece shining, you don’t want to overdo it.
How do you stop silver from tarnishing?
Here are a few tips to stop or slow down tarnishing.
Proper Storage
Always store your silver pieces separately to prevent them from scratching each other. Store them in different bags. These bags should be dry and airtight and should be kept away from direct sunlight because heat also accelerates tarnishing.
Also, when storing your silver pieces, place a piece of chalk in your jewelry box or bag. This is because chalk absorbs moisture. So, this will eliminate dampness from your silver or storage box.
Avoid storing your silver piece in rubber or plastic bags and wooden boxes. This is because these substances can accelerate silver tarnishing.
Avoid exposure to moisture and other chemicals
Always remember to take off your silver piece when washing your hand, swimming, taking a shower, cooking, or exercising. Moisture speeds up tarnishing.
Also, when silver is exposed to oils from your skin, your makeup, or cosmetics, it causes it to tarnish faster. So, if your silver piece is exposed to any of these, be sure to clean it immediately.
Don’t leave your silver piece lying around
Always put away your silver piece when you’re not wearing or using it. It is important to limit its exposure to air and moisture as they cause it to tarnish over time.
Can you clean tarnished silver?
Yes, you can clean tarnished silver. When silver tarnishes, the black layer is just on the surface of the silver piece. So, you can get rid of this layer. Here are a few easy and inexpensive methods to clean your tarnished silver.
1. Using baking soda and aluminum foil: you will need a large bowl, aluminum foil, baking soda, and boiling water for this. Get a large bowl and line the insides with a sheet of aluminum foil. The shiny side should be up in the bowl.
Place the tarnished silver on the foil in the bowl and pour the boiling water over it. Then, sprinkle a good amount of baking soda on it (at least a few tablespoons). Once the silver is clean, remove it from the solution and wash the silver piece properly in warm soapy water and dry it with a soft anti-tarnish cloth.
2. Using baking soda and hot water: you’ll need a soft sponge, hot water, and baking soda for this method. Get a soft sponge and wet it with hot water and squeeze.
Sprinkle one of two tablespoons of baking soda onto the sponge. Use the sponge to rub the tarnished silver gently until it’s clean. Now, wash the silver piece with warm soapy water and dry with a soft cloth.
3. Using vinegar: you’ll need vinegar, warm water, and baking soda for this. Get a large bowl. Pour the warm water into the bowl and mix with 1/2 cup of white vinegar and 2 tablespoons of baking soda. Put the tarnished silver in the solution and let it sit for 2 to 3 hours. Then, take out the silver piece, rinse with cold water, and buff dry with a soft cloth.
4. Using laundry detergent: You’ll need a large bowl, hot water, and laundry detergent. Get a large bowl and pour the hot water into the bowl. Pour 1 small cup of laundry detergent into the bowl. Place the tarnished silver into the solution and leave it for 5 to 7 minutes. Now, take out the silver piece and buff it dry with a soft cloth.
Can you use toothpaste to clean tarnished silver?
Toothpaste has been known to be used for a lot of other things besides cleaning the teeth. One of those things is cleaning tarnished silver. Yes, toothpaste can be used to clean tarnished silver. Here’s how;
- Get a non-gel and non-abrasive fluoride toothpaste and a soft damp cloth.
- Squeeze a pea-sized amount of the toothpaste on a soft damp cloth.
- Rub it onto the silver piece in a circular motion until the toothpaste makes an almost black appearance. Let it sit for 2 to 5 minutes.
- Rinse off the toothpaste and dry the silver piece with a soft cloth.
Tarnish remover for silver
While there are a couple of home remedies for silver tarnishing, there are also some products that are effective for cleaning silver tarnish. I can recommend a few.
The best silver cleaner based on recent ratings is the Weiman silver polish and cleaner. What makes Weiman polish cleaner so special? It is a non-scratch silver cleaner. It leaves a protective tarnish coating that delays tarnish from returning. It is ammonia-free which makes it safe to use on all types of silver.
Another good one is Goddard’s silver polish foam. It is very easy to use and also leaves a tarnish-resistant barrier to delay the silver from tarnishing. It is safe for sterling silver, sheffield plate, and electro-plated nickel silver.
Other related questions
What causes silver to tarnish so quickly?
Exposing the silver piece to moisture and high heat can cause the silver to tarnish quickly. So next time you want to go for a swim or wash your hands, remember to take off your silver jewelry. Air drying a silver piece or storing it in a hot place can also cause it to tarnish quickly. In addition, certain materials and food substances such as rubber, cardboard, latex, eggs, spinach, onions, garlic, and paper, can cause tarnishing if exposed to silver for long.
Does sunlight cause silver tarnishing?
When silver is exposed to direct sunlight, it can tarnish quickly. Certain materials in the atmosphere can break down the coatings on your silver piece or cause deterioration. A good example is hydrogen sulphide (H2S).
Can fake silver tarnish?
While pure silver does not tarnish, fake silver will lose its shine with time. They are made of cheap alloys that cause them to oxidize and change color over time. Fake silver (usually just silver-plated metals) can turn your skin green and can lead to allergic reactions like rash or itchiness for some people due to the metals they are made with or their coatings. For any fake silver piece, when it tarnishes, it may never return to its original shine but this is the opposite for real silver pieces.
Conclusion: Is Silver Tarnishing A Chemical Change?
To conclude, silver tarnishing is a chemical change. This occurs when silver gets damp or exposed to gaseous compounds containing sulfur. This often leads to discoloration.
Tarnishing is absolutely normal, inevitable, and can be reversed. Tarnishing is accelerated by moisture, air drying, improper storage, exposure to high heat, exposure to sulfur-containing substances and skin oils.
To prevent silver tarnishing, store your silver pieces properly and keep them away from everything mentioned above. If you do this, your silver piece can last years without tarnishing.