Chemical Curiosities: Acid vs. Base’s Epic Rematch

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In 2020, Eyewire HQ brought you the original Acid vs. Base competition. This week, in the spirit of Chemical Curiosities, we’re coming back to the pHantastic power of pH: not only to give Team Acid a fresh chance at victory and Team Base a chance to hold on to their title, but also to give a more in-depth lesson about what pH actually measures on an atomic and molecular scale, and why chemical reactions between opposite ends of the pH scale are so… well, reactive.

Traditionally short for “potential of hydrogen,” pH is a scale for measuring how many hydrogen ions are concentrated in a given solution. To understand what that really means, first you need to know that an ion refers to an atom whose electromagnetic charge has been made positive or negative by losing or gaining electrons beyond the normal amount of electrons that atom would normally have. Because that normal amount of negatively-charged electrons is meant to be balanced out by the atom’s nucleus being positively charged, under those normal circumstances an atom’s charge is neutral, 0; so if you skew the number of electrons, this will imbalance the charge and make it no longer 0. When you have a positively-charged ion (technically a cation), it lacks electrons and “wants” to gain enough to be a complete, normal atom again; when you have a negatively-charged ion (technically an anion), it has more electrons than it needs to be a complete, normal atom, so it may shed them if possible.

So that’s what’s up with an ion. Now consider the implications of a hydrogen ion. A normal hydrogen atom has just one electron, which is the least of any element in the Periodic Table. You can force a hydrogen atom to become a negatively-charged ion by adding additional electrons, but something distinctive happens when you make a hydrogen atom into a positively-charged ion: suddenly you have an ion that’s not just missing electrons, but has no electrons! Although you can strip all the electrons away from other elements in theory, it’s easiest to do this with hydrogen. And as you might imagine, when an ion has no electrons whatsoever, it’s very, very “interested” in receiving an electron.

This makes positive hydrogen ions (notated as H+) bond extremely easily with other available atoms or full-blown molecular structures. When these bonds are formed, it constitutes a chemical reaction, which may sometimes have very mild indicators but may also become very intense, depending on exactly how many H+ ions are present and what’s available for them to bond with. If a concentration of H+ meets with a substance that has very little H+, electrons may be furiously exchanged. The chemical reaction may also cause destruction to involved substances if those substances are sensitive to a certain amount of H+ exposure; there can also be a reverse version of this wherein substances containing a certain amount of H+ are damaged by coming into contact with substances that markedly lack H+.

Bearing all of this in mind, the pH scale was invented to gauge the relative potential for a reaction involving H+, though it does make certain assumptions, namely:

  • All substances being measured are aqueous solutions, that is where something’s been dissolved in water.
  • The temperature during measurement is 25ºC (77ºF).

pH is also calculated logarithmically, and it measures an inverse relationship. We’ll spare you the math here, but what we mean by the last part is that the more H+ there is, the lower its pH value. This is the definition of being an acid or acidic substance. The less H+ there is, the higher the pH, which is the definition of being a base or alkaline substance. If it sounds confusing to picture something with very low pH being highly reactive, just remember that something with very high pH is also highly reactive. Strong acids and strong bases alike can transform their surroundings, and when they combine… watch out! Also, even weaker acids and bases still can produce noticeable reactions with each other, or exhibit mildly corrosive effects on their environments over time. Let’s return now to the same team details that we had three years ago, to analyze specific examples.

Acid

Of the many acidic substances we profiled the first time around, lemon juice and vinegar stand out in a special way. Why? They make great cleaning products for most surfaces in your home, and they’re extremely environmentally friendly and safe for you! Dilute them together in some water, spray them on what you’re cleaning, then wipe or scrub away. You may be amazed by their effectiveness. Also, while the lemon juice will add to the effect of the vinegar, it will also help mask that vinegar smell. Just bear in mind that some surfaces are too sensitive to these acids and will suffer damage, so do your research — for example, polishing glass with vinegar is fine, but polishing silver is not!

Base

Remember how we mentioned baking soda as a base in 2020? Well, plot twist: this is a great cleaning product too! Make a paste out of baking soda and water and you can safely clean with it. Often it will work on the same surfaces that vinegar does, as its molecules will “scrub” in an opposite but similarly effective way. Of course, when baking soda paste dries, it leaves a residue, so you can’t just drop it on a carpet stain. But it works well on many household surfaces you can fully wipe up afterward. It’s great for cleaning caked-on gunk out of your oven, and in fact, as long as your silver isn’t super high-end, you can clean that with baking soda. Line a container with aluminum foil, add some baking soda, and pour enough water on top to make a bath for your sterling silver jewelry. Leave the silver there for 30 minutes to a few hours, and you’ll see any tarnished areas look a lot better!

Another pH Trick To Try At Home

One other thing we brought up in the original Acid vs. Base post is how different types of garden plants benefit from soil with different pH levels. So it’s great to know what soil pH you need for your gardening plans. But you can’t do much if you don’t know the existing pH of your garden’s soil! If you want a precise number, you’ll need to buy a test kit, which is pretty cheap and easy — but if you’re just looking for an overall idea of whether your soil is acidic vs. alkaline, you can DIY a simple experiment. Collect a soil sample and split it in half. Then take two small bowls. Put vinegar in one, and make a baking soda bath in the other. Drop one soil sample half into each bowl and look for which soil sample “fizzes” more when it comes into contact with the substance inside. If it fizzes more with the vinegar, your soil is reacting because it’s alkaline soil. If it fizzes more with the baking soda, your soil is reacting because it’s acidic soil. If the reactions seem about the same, your soil’s pH is probably close to neutral.

So now you know a lot more about Acid vs. Base. Where do your loyalties lie this time? Make your choice and get ready to see whether Team Acid will snag its first win, or whether Team Base will be the double victor on Eyewire! The competition starts at 11:00 AM EST on 2/20 and goes for 48 hours! Bonus information is detailed in your notifications.

Swag: The top scoring player on the winning team wins the choice of a notebook or a mug, plus a sticker/magnet set! Second and third place will each also win a sticker/magnet set.