They are both about the same so it depends on which is on sale. Aluminum foil and acid will remove rust. The foil is softer than many metals so it won’t scratch them but it is harder than rust so it will abrade it.
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Drinking soda can contribute not only to this change in color but also to the overall strength of the enamel. Since
enamel starts to dissolve at 5.50, anything at that level or closer to zero will certainly do damage, also breaking through to the dentin, which is the next protective layer lying directly beneath the enamel. All the cosmetic dentistry in the world cannot bring back enamel. Once you lose it, your body cannot make any more.
Coca-Cola pH Level
The pH of Coke is
2.52. For reference, this is close to the acidity level in phosphoric and sulfamic acid, which are at a pH level of 2. This is also the same pH as lemons. Therefore, drinking a lot of Coca-Cola will start to take a toll on your teeth.
Pepsi pH Level
There's definitely a lot of debate regarding what's better: Coke or Pepsi. While the taste may be different, the pH levels are extremely close. Pepsi has a pH level of
2.53, which means that it is only a tiny bit less acidic than Coca-Cola.
7UP pH Level
Another popular drink is 7UP. 7UP, despite its green packaging that gives it a more volatile appearance, is actually less acidic than Coke and Pepsi with a pH level of
3.20. However, this is still highly acidic when it comes to your teeth.
Mountain Dew pH Level
Unlike 7UP, which isn't actually green, many would argue that Mountain Dew has a radioactive green color. Despite this, it's on par with 7UP as far as its pH level, which is
3.22. Therefore, it's still less acidic than Coke and Pepsi too.
Sprite pH Level
Sprite is similar to 7UP, but it might be somewhat of a healthier choice of soda compared to others. This is because the Sprite pH level is
3.29.
Dr. Pepper pH Level
Dr. Pepper is up there with Coke and Pepsi in terms of its acidity level. Despite being loved by many, you should think twice before opting for a Dr. Pepper, as the pH level is
2.89. However, this is still less acidic than the similar-tasting cherry Coke, which has the same pH as Coke at
2.52.
Root Beer pH Level
If you want to choose the safest soda, then
root beer is your best bet.Root beer has the lowest acidity levels of any other soda, averaging between 4 and 5. A&W root beer has a pH level of
4.75, and Barq's is at
4.47. Root beer is said to be less acidic because it doesn't contain phosphoric or citrus acids and is often not carbonated. This makes it less acidic than some juices. For example, the pH of orange juice is around 3 depending on the brand.
ref:
Acidic Levels in Different Sodas
The acid level of other foods are here.
pH Values of Common Beverages and Foods - Nutrients Review
And what's kind of nice at the holiday table are flutes of champagne and a splash of cranberry juice, and a fresh cranberry. 
