Free Science / Chemistry
The Chemistry of Everyday Life: How Common Items Work
Exploring the chemistry of everyday life and how common items work, including soap, water, carbonation, batteries, non-stick coatings, and sunscreen.
Welcome to Listen Learn Pods, where we dive deep into fascinating topics to keep you informed and entertained. Today's episode takes a journey through the mysterious world of chemistry. Specifically, we're going to explore the chemistry of everyday life and how common items work. By the end of this podcast, you'll have a better understanding of the world around you, down to the molecular level.
Let's begin by looking at soap and how it functions in the cleaning process. Soap is made from fatty acids that have been chemically altered using a base like lye, which is a strong alkaline substance. The fatty acids are broken down into molecules called surfactants, which have two distinctive parts: a hydrophilic (water-loving) head and a hydrophobic (water-hating) tail.
Here's where the magic happens: when you mix soap with water, the hydrophobic tails gather around grease and dirt particles, while the hydrophilic heads stay in contact with the water. This creates a spherical structure known as a micelle, which surrounds and separates the dirt and grease from the surface you're trying to clean. As you continue to scrub and rinse, the micelles are washed away, taking the dirt and grease with them.
Speaking of water, have you ever wondered why it's so great at dissolving things? Water is a polar molecule, meaning that it has a positively charged end and a negatively charged end. This allows it to surround and interact with other polar molecules, breaking down their molecular bonds. Additionally, water can dissolve many ionic substances, like common table salt. When salt, which is composed of sodium (Na+) and chloride (Cl-) ions, is dropped into water, the positively charged sodium ions are attracted to the negatively charged oxygen atoms of the water molecules, while the negatively charged chloride ions are attracted to the positively charged hydrogen atoms. This results in the salt crystals breaking apart and dispersing evenly in the water, creating a uniform solution.
Now let's move on to a topic that's literally refreshing: the chemistry behind the carbonation in our favorite fizzy drinks. The distinctive bubbly sensation comes from the presence of carbon dioxide (CO2) gas dissolved in the liquid. When the pressure inside the container is released upon opening the bottle or can, the CO2 starts to come out of the solution in the form of bubbles, a process called effervescence.
In some cases, the carbonation is a natural byproduct of fermentation. For example, in beer and champagne, yeast feasts on sugars and produces CO2 as a waste product, imparting carbonation to the drink. Alternatively, in most soft drinks, carbonation is added artificially by dissolving CO2 in the liquid under high pressure.
Now, we all know that batteries power a wide variety of our everyday devices. But have you ever considered how these little energy suppliers work? At their core, batteries rely on chemical reactions to produce a flow of electrons, which we can harness as electricity. Most batteries consist of a cathode (positive terminal) and an anode (negative terminal) submerged in an electrolyte solution.
The chemical reaction taking place in the battery forces electrons to move from the anode to the cathode, creating an electric current. When we connect a device like a flashlight to a battery, we complete an external circuit, allowing the flow of electrons from the anode through the device and then back to the cathode. As the battery's chemicals get used up in the reaction, its ability to produce a current diminishes, which is why batteries eventually run out of power.
Ever wonder how that non-stick coating on your frying pan works so well? The most common non-stick surface is made using a polymer called polytetrafluoroethylene, or PTFE. You may know it better by its brand name, Teflon. PTFE has a unique structure that features carbon atoms surrounded by fluorine atoms, which form an incredibly strong bond. The strength of these bonds, along with the fact that fluorine atoms are very unreactive, make PTFE highly resistant to sticking or bonding with other substances.
Not only does this result in a smooth, non-stick surface that food slides right off of, but it also makes PTFE resistant to chemical corrosion, enabling it to withstand high heat and other harsh cooking conditions. Keep in mind, though, that when heated to extremely high temperatures, PTFE can break down and release potentially toxic fumes, so it’s important to cook responsibly and follow the manufacturer's guidelines.
Lastly, let’s look at how sunscreen helps protect our skin from harmful ultraviolet (UV) rays. Sunscreen contains a mix of organic and inorganic compounds that absorb, scatter, or reflect UV radiation. Some of these compounds are designed to specifically absorb UVA or UVB rays, which can cause skin aging, sunburn, and even skin cancer.
Organic compounds in sunscreen, like avobenzone and oxybenzone, work by absorbing UV radiation and then re-emitting it as lower-energy, non-harmful heat. Inorganic compounds, such as zinc oxide and titanium dioxide, act as physical barriers on the skin, reflecting or scattering the UV radiation to prevent it from being absorbed. The sun protection factor (SPF) you see on sunscreen labels is a measure of how much UVB radiation the sunscreen can block.
And with that, we've wrapped up our journey through the chemistry of everyday life. From the soap in our showers to the sunscreen on our skin, we’ve explored the science behind some fascinating common items. We hope you enjoyed this episode of Listen Learn Pods, and we can't wait to join you on our next adventure.
Goodbye for now, and stay curious!