Baking a cake was never so educational – or so fun! Come into the kitchen with Ask Science and learn about the four fundamental states of matter.
Many of us grew up hearing about the 3 states of matter: solid, liquid, and gas. You might be surprised to learn that there are actually quite a few more than 3 states of matter. We might try to excuse ourselves from knowing about these other states of matter because they must be very uncommon, right? Unfortunately, one of these lesser-known states of matter isn’t uncommon at all. Plasma is considered the fourth, fundamental state of matter and is actually the most common state of matter in the universe. Go figure!
Let’s take a look at how we interact with these different phases of matter when we bake a cake. So grab your favorite cake recipe and follow me to the kitchen.
It’s pretty easy to identify the solids in our cake baking exercise. In solid matter, the molecules that make up a substance are packed together very tightly. One of the effects of this is that solids typically have a definite shape that resists being changed.
As we reach for our mixing bowl, hand mixer, measuring spoons, and chef’s hat, everything we’ve gathered together is a solid.
The molecules of a liquid are packed together less tightly than that of a solid, which allows them to slide around quite a bit. This means that a liquid can change its shape to fit its container. However the overall volume (or total space the liquid takes up) generally doesn’t change, as long as the temperature and pressure stay the same.
Liquids are also pretty easy to identify, milk and water for example are obviously liquids we’ll need for baking our cake.
Unlike solids and liquids, matter that is in the gas state typically doesn’t retain its state. The molecules of a gas aren’t packed tightly together at all and tend to float around wherever they want, completely independently from one another.
If you have a gas-powered oven, then when you turn your oven on to bake the cake, a flammable gas (either propane or methane) is piped into your oven to provide fuel for the fire. If you have an electric oven, take comfort in the fact that the reason mixing baking soda and the milk allows your cake to rise, is because acids and bases produce carbon dioxide, which in this case is in a gas state.