In my opinion, it is different because sugar and water are polar substances, so sugar can dissolve easily. However, salt can be polar and nonpolar, so it may be difficult to dissolve in water. Polar substances dissolve in polar substances. Nonpolar substances dissolve in Nonpolar substances. Nonpolar substances cannot dissolve into polar substances.
Sugar looked clear when dissolved, but salt got cloudy right after the 1 st teaspoon. Predictions made before the activity, I believed that both sugar and salt will look the same after dissolved in water, but it turns out the sugar looks clear. I believe the polar nature of the water molecule contributes to its dissolving prowess. These positive and negative areas on water molecules are also attracted to the positive and negative areas of the molecules or ions of other substances.
This is the key to water's great ability to dissolve other substances. Analyzing data in 9—12 builds on K—8 and progresses to introducing more detailed statistical analysis, the comparison of data sets for consistency, and the use of models to generate and analyze data. Skip to main content. Home Salt vs. Sugar — A Dissolving Problem Salt vs. Sugar — A Dissolving Problem. Teacher reflections Because of the asynchronous flow of the remote learning period, this was challenging to be able to fully communicate with my students during this activity to fully understand their chemical thinking as they were working.
Remote learning During the Remote Learning session, Google Classroom was the primary tool for instruction and organization of learning materials. Examples of student work Pre-activity questions 1. Why do you think substances dissolve in the first place? How does a substance dissolve? You may include a picture to help illustrate your explanation. Student 1 Saturated — Holding as much water or moisture as can be absorbed; thoroughly soaked.
General Safety. Science Practice: Analyzing and Interpreting Data. Summary: Analyzing data in 9—12 builds on K—8 and progresses to introducing more detailed statistical analysis, the comparison of data sets for consistency, and the use of models to generate and analyze data. In the years that you've been using salt and sugar on your foods, you've probably noticed that each piece of salt-which actually is a crystal-is a little smaller than each piece of sugar, which also is a crystal.
The problem you'll be attempting to solve in this experiment is whether sugar or salt dissolves faster when mixed into various liquids.
Does the size of the pieces affect how quickly they mix with the liquid? When you dissolve sugar or salt in a liquid-say, water-what happens is that the sugar molecules move to fit themselves between the molecules of water within a glass or beaker. The illustration below shows how the different molecules are arranged in the container. In your experiment, you'll see how salt and sugar molecules move within different liquids and dissolve at different rates.
You also could consider one of the following titles for your project:. Whatever name you choose is fine. Let's take a minute now to consider why this project is a valuable use of your time. And when the excessive solute has been dissolved by heating the solution, it's said to be supersaturated. The point of this experiment, in addition to learning whether salt or sugar dissolves faster in various liquids, is to learn how molecules interact in a solution.
As you saw in the preceding illustration, the water molecules take up most of the room in the container. But there is still some available space in which the sugar or salt molecules can fit. Through your experiment, you'll learn how fast the sugar molecules fit into those spaces, as compared to the salt particles.
Knowing this will help you better understand the process that occurs as a substance dissolves. The control in your experiment will be water. The other liquids in which you dissolve salt and sugar will be the variables.
Remember when you conduct your experiment that it's very important that the liquids you use are all the same temperature. You already learned that sugar dissolves faster in a warm liquid than in a cool one, so you know it wouldn't be an accurate experiment if some of the liquids you use are warm and some are cold. The temperature of the liquid would become a variable. Therefore, all the liquids you use-including water-should be at room temperature.
If you normally keep them in the fridge, be sure to allow them to sit out on the counter overnight until they are all the same temperature. To give you a little more flexibility when you conduct the experiment, you may choose the liquids in which you'll dissolve sugar and salt. There's no point in having to go out and buy additional liquids if you've already got what you need.
Just make sure you choose liquids that are different from each other in taste, color, odor, and purpose. You'll also need to select those that allow you to observe the salt and sugar as it dissolves. If you use milk or orange juice, for example, you won't be able to watch the salt and sugar dissolve. Some suggestions for liquids to consider are:. All of these are commonly found around the house, perhaps saving you a trip to the store.
Now that you know how solutions are formed and some of the factors that will affect the speed at which the sugar and salt you'll be using will dissolve, you should be able to make a good guess as to which one will dissolve faster. While you won't know until after your experiment if properties of the different liquids you choose will affect the rate at which the salt and sugar dissolve, you do know that salt crystals are generally smaller than sugar crystals.
And you know that the temperature of the liquids will not be a factor in your experiment. Just try to use your past experiences, the information you've read earlier in this section, and your common sense to come up with a sound hypothesis.
Remember that your hypothesis must be stated as an objective sentence, not a question. So go ahead and -make your guess as to whether the salt or sugar will dissolve faster, and let's get started with the experiment.
Some liquids suggested for use in this experiment are white vinegar, club soda, ginger ale, glass cleaner, rubbing alcohol, apple juice, lemonade, and tea. We also think that stirring was probably a factor of the uneven times.
For example, the powdered sugar got 56secs and 18secs. Does vinegar dissolve sugar? Vinegar is acetic acid, which reacts only with certain kinds of substances and sugar is not one of them. In fact candy might dissolve more slowly in vinegar. Since acetic acid molecules don't dissolve sugar as well as water. Acids don't break up compounds in your food.
What happens to sugar when mixed with water? The sugar molecules cannot go away but they can disperse in the water.
They will still be sugar molecules just not attached to any other molecules of sugar. Why isn't my sugar dissolving? Note that if you add too many sugar cubes to the cup of water, they might not dissolve completely because the water may become saturated with the solute. If you have added too much sugar by mistake, transfer the contents into a larger cup or container, add more water, and stir to help the sugar dissolve faster. What temperature of water will dissolve sugar the faster?
As the temperature increases, more and more sugar can be dissolved, but only slightly more salt can be dissolved. About g of sugar will dissolve.
Which dissolves faster salt or sugar? For a given solvent, some solutes have greater solubility than others. For example, sugar is much more soluble in water than is salt. But even sugar has an upper limit on how much can dissolve. How do you dissolve sugar in water?
Put a sugar cube into the cold water and stir with the spoon until the sugar disappears.
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