Chemistry is everywhere. It’s active in the air in our lungs, the products on our bathroom shelf, and the food on our plate. Even deionised water is considered a chemical.
Still, chemistry remains one of the most misunderstood subjects in the natural and man-made world.
Misconceptions about chemicals and basic chemistry processes spread easily, often starting in the primary school classroom. They’re reinforced by fear-based advertising and the false perception that chemistry is purely academic.
The truth is, chemistry is at the core of all life on Earth. It’s the bridge that connects biological processes with physical matter. Understanding it provides invaluable insights into everything from health and medicine to products essential for daily life.
In this post:
Key Takeaways
Many of the most common chemistry misconceptions result from oversimplification in schools and the micro level at which chemical reactions occur
Acids can be dangerous, but many provide health benefits and are used in everyday products
Chemical reactions are either instantaneous or occur over long periods of time
Water exists in three states and can change form when temperature and pressure fluctuate
Matter is neither created nor destroyed during chemical reactions
Some chemicals are harmful to humans, but many play an essential role in our health and daily lives
How Misconceptions About Chemistry Start
Many common chemistry misconceptions arise from oversimplifying ideas. A primary science curriculum may take a shortcut to explain a complex idea, eliminating crucial context. This incomplete information soon becomes fact in children’s minds.
Misconceptions also stem from the fact that we often can’t see chemistry in action. When chemical reactions happen at a micro level, we fill in the knowledge gaps with assumptions.
Understanding the source of these misconceptions is the first step toward scientific awareness. With a clearer picture of how chemicals and chemistry work, we can make informed decisions about the products we use and the foods we eat. We can also better understand the world around us.
Let’s investigate five common chemistry misconceptions and discover the truth.
1: All Acids Are Dangerous
Acid has a horrible reputation. It’s perceived as a highly toxic chemical that causes severe injury or death. Horror films and television shows perpetuate this fear.
It’s important to note that many forms of acids are dangerous. However, acids exist across a broad spectrum of concentrations. Many are harmless, and some are good for us.
The citric acid found in lemons, limes, and berries is a beneficial antioxidant. Amino acids in protein-rich foods promote muscle health.
Hyaluronic and lactic acids are used in skincare products to support hydration and remove dead skin cells. We even have gastric acid in our stomachs that aids digestion.
Highly corrosive and reactive acids are the ones to be careful around. They have low pH levels, which means they can cause severe chemical burns. Examples include nitric acid, sulfuric acid, and hydrochloric acid. Each has a wide range of uses across many industries.
2: Chemical Reactions Are Always Instantaneous
A chemical reaction occurs when one or more substances (reactants) undergo a transformation resulting in one or more new substances (products) with different properties. During this process, chemical bonds break, and atoms get rearranged.
Children’s science shows often include experiments that demonstrate fast, loud, or colourful chemical reactions. They’re fun, but that’s not the whole story. Some chemical reactions occur over days, months, or years.
Whether a chemical reaction is instantaneous or gradual is largely based on activation energy. This is the energy barrier that reactants must overcome to become products.
Instantaneous chemical reactions occur when the activation energy is either low or nonexistent. A good example is mixing silver nitrate and sodium chloride. The activation energy is low because the ions are already floating in water, meaning they don’t need to break chemical bonds to react.
Gradual chemical reactions occur when high activation energies are present. Rusting is a good example. Breaking the strong metallic bonds of iron so it can react with oxygen and water requires significant energy.
3: Water is Always a Liquid
Water is precious. We drink it to survive and use it for countless things every day – almost always in liquid form. But the idea that water is always liquid is one of the most common chemistry misconceptions.
Water exists in three states – solid, liquid, and gas (vapour). The state depends on temperature and pressure, and states can fluctuate between each other.
The solid state is obvious – water freezes at 0°C and turns to ice. Seems simple enough, but there’s more going on behind the scenes. Hydrogen bonding forms a hexagonal crystal lattice, which is denser than liquid water. That’s why ice floats.
The transition from liquid to gas is a little more complex. Water begins to boil at 100°C. Bubbles form when the vapour pressure overcomes the atmospheric pressure.
A common misconception is that a pot of boiling water on a stove continues to rise in temperature. The truth is that boiling water in liquid form only continues to rise under increased pressure, such as in a pressure cooker. On a normal stove, the additional heat turns the water from a liquid to a vapour.
Vapour that escapes boiling water carries thermal energy away from the liquid. As it loses energy, molecules slow down and get closer to each other, turning the vapour back into liquid. This is why condensation builds up in the area above the boiling pot.
4: Chemicals Are Harmful By Nature
Many people perceive chemicals as villainous substances that present a threat to the environment, animal life, and human health. They represent artificiality and toxicity. This is one of the most common chemistry misconceptions.
A chemical is any substance with a defined composition. They’re organic and made-made, essential to life and deadly.
Everything that exists is made of matter, and matter is made of chemicals. Oxygen and water are chemicals. Organic compounds like salt and sugar are also considered chemicals. We consume them every day.
Dosage and exposure determine the toxicity of chemicals. It has nothing to do with whether the chemical is natural or synthetic. Consuming too much water can cause a fatal drop in sodium. Conversely, exposure to certain synthetic chemicals is safe at low levels.
Harmful chemicals are also part of daily life. They’re in household cleaning products, cigarettes, paint, plastics, cosmetics – the list goes on. Whether they’re harmful or not depends on how we use them.
5: Chemical Reactions Create Mass
Many primary school science experiments explore basic chemical reactions. The fizzy volcano demonstrates how an acid (vinegar) and a base (baking soda) create a gas (carbon dioxide).
The result of the volcano experiment is fun for kids. It’s also the basis for one of the common chemistry misconceptions – that a chemical reaction creates something.
The law of the conservation of mass debunks this misconception. It states that matter can’t be created or destroyed during a chemical reaction. Atoms get rearranged, but aren’t lost or gained. This means that the total mass of vinegar and baking soda is equal to the total mass of the fizzy lava.
The law works the same way in the opposite direction. When a campfire burns wood down to a pile of ash, it hasn’t destroyed anything. The total weight of wood and oxygen equals the total weight of smoke, gas, and ash.
Conclusion
These common chemistry misconceptions are deeply ingrained in our culture. Understanding the truth behind them is a powerful tool. It enables us to see the world more clearly and make better decisions in our daily lives. By embracing the complexity of chemistry, we can move beyond fear and develop a healthier, more informed relationship with the science that underlies all life.
