Summertime is perfect for picnics with sweet iced tea and yummy fruit salad. But have you ever noticed that these foods have something in common? They’re both mixtures! A mixture is made by combining two or more different things. Let’s explore the world of mixtures with a little science at our picnic.
Anytime you combine two different things, you create a mixture. For example, strawberries and bananas or raspberries and blackberries are mixtures. Even if you mix something unusual like cantaloupe and Legos (which you shouldn’t eat!), it’s still a mixture.
Let’s look at some examples. If you mix sand and water in a glass, you’ll get a mixture. Over time, the sand will settle at the bottom. But if you stir sugar into water, the sugar seems to disappear. It doesn’t really vanish; it spreads evenly throughout the water. This type of mixture is called a solution.
Solutions have two main parts: the solute and the solvent. The solute is the substance that dissolves, like sugar, and the solvent is the substance in which the solute dissolves, like water. Solutions can be made from different states of matter. For example, the air we breathe is a solution of gases, and soda water is a solution of carbon dioxide gas in liquid water.
Importantly, mixing things in solutions doesn’t create a new substance. You can separate them back into their original parts. For instance, if you leave soda water open, the carbon dioxide will bubble away, leaving plain water behind.
Not all substances dissolve easily. The ability of something to dissolve is called solubility. Sand has low solubility in water, while sugar has high solubility. However, there’s a limit to how much solute can dissolve. If you keep adding sugar to water, eventually no more will dissolve. This is called saturation.
Let’s look at our picnic table. The fruit salad is a mixture of different fruits, but it’s not a solution because the fruits aren’t evenly distributed. You might get only strawberries or only bananas with each spoonful.
On the other hand, sweet tea is a solution. The water and sugar are evenly spread out, so every sip contains both. You can even separate the tea by heating it until the water evaporates, leaving the sugar behind.
At our picnic, we learned that a mixture is made by combining two or more substances. When the particles are evenly distributed, it’s called a solution. Solutions can involve substances in the same or different states of matter. The solute is what dissolves, and the solvent is what it dissolves into. Remember, solutions and some mixtures don’t create new substances, even if it seems like they do.
Now, let’s enjoy the rest of our picnic before the ants carry it all away!
Mix and Match Experiment: Gather a few household items like salt, sugar, sand, and water. With the help of an adult, try mixing each item with water in separate clear cups. Observe what happens to each mixture. Does the item dissolve, or does it settle at the bottom? Discuss which ones are solutions and which are not. Can you think of other items to test?
Fruit Salad Sorting: Create your own fruit salad using different fruits like apples, grapes, and oranges. Mix them in a bowl. Now, try to separate them back into their original groups. Talk about how this is different from separating a solution. Why is it easier to separate the fruits than to separate sugar from water?
Question Time: Think about your favorite drink. Is it a mixture or a solution? Why do you think so? Discuss with a friend or family member how you could separate the parts of your drink if you wanted to. What would happen if you left it out in the sun?
