This acid breaks down the enamel in our teeth. Because sucrose contains so much energy, over-consumption of it can lead to weight gain.
Over-consumption of salt can lead to high blood pressure, fluid retention and certain metabolic disturbances.
Sly Tutor has been a writer since and has had work appear in the "Altoona Mirror" newspaper. Related Articles Is Sucrose an Aldose? What is Glucose Made Of? Heat Absorption Properties of Salt. Question to Investigate Can you identify the unknown crystal by the way it looks? Add at least two teaspoons of each crystal to its labeled cup. Label the center Unknown. Place small samples of Epsom salt, table salt, sugar, MSG, and the unknown on the labeled areas of the construction paper.
Use a magnifier to look carefully at each type of crystal. Expected Results All of the crystals are white, but some are more transparent or opaque than others. Discuss student observations and have groups plan how they might conduct a solubility test to identify the unknown.
Ask students: What do you notice about each crystal? Include any similarities or differences you notice among them. Students should describe physical properties such as the size, shape, color and texture. They should also describe whether the crystals are shiny, dull, transparent, or opaque. Can you identify the unknown yet? Students should not have enough evidence to correctly identify the unknown at this point.
They will discover this by the end of this lesson. Have student groups share their ideas for a solubility test and consider how each plan controls variables. Ask students: Is it better to use the same volume like a teaspoon or 5 mL or the same mass like 5 g of each crystal? Tell students that you will do a demonstration that will help them see whether they should use a volume or mass measure so that they can dissolve the same amount of each crystal in water.
Do a demonstration to show that mass is better than volume in measuring equal amounts for a solubility test. Question to Investigate Is it better to measure the same volume or same mass of each crystal when conducting a solubility test to identify an unknown?
Materials for the Demonstration 2 clear plastic cups Cereal balls Kix work well Zip-closing plastic bag quart-size storage-grade Balance Teacher Preparation Fill two clear plastic cups completely with cereal balls.
Procedure Hold the cups filled with cereal up so that students can see that both have about the same amount of cereal in them.
Place the cups in the center of each end of a simple balance to prove to your students that both contain the same amount of cereal. Ask students to make a prediction: I am going to crush the cereal balls in one cup. Do you expect the height of cereal in this cup to be higher, lower, or the same as in the other cup? Students will probably say that the crushed cereal will not take up as much room in the cup.
Pour the cereal from one of the cups into a storage-grade, zip-closing plastic bag. Get as much air out as possible and seal the bag. Place the bag on the ground, and crush the cereal thoroughly with your foot. Once the cereal is pulverized, open the bag, and pour the crushed cereal back into the cup. Ask students: Which cup contains more cereal? Students will realize that both cups contain the same amount of cereal, but some may have an urge to say that the cup with the cereal balls contains more cereal.
Was any cereal added or removed from either cup? Point out that even though the crushed cereal takes up less space, it is still the same amount of matter cereal as was in the cup before it was crushed. How could you prove that these two cups contain the same amount of matter? Students should suggest placing the cups on a balance as you did before. Expected Results Even though the volume of cereal balls is greater than the volume of crushed cereal balls, the cups will balance on the scale.
Relate student observations in the demonstration to the five crystals they will dissolve in water. Ask students: In the solubility test you will do, you will need to measure equal amounts of the five crystals.
How will you measure equal amounts? After this demonstration, students should realize that measuring mass for a solubility test is better than measuring by volume. Have students weigh five grams of each of the crystals for the solubility test. Label the 5 larger clear plastic cups the same way. Weigh 5 g of each crystal and place each in its small labeled cup. Have students dissolve the four known crystals and the unknown in room-temperature water.
Question to Investigate Can you identify an unknown using a solubility test? Materials for Each Group Graduated cylinder 5 g each of salt, Epsom salt, MSG, sugar, and unknown coarse kosher salt 5 clear plastic cups Water Procedure Use a graduated cylinder to add 5 mL of room temperature water to each empty clear plastic cup.
Match up each pair of labeled cups so that each cup of crystal is near its corresponding cup of water. With the help of your lab partners, swirl each cup at the same time and in the same way for about 20 seconds and observe.
Swirl again for another 20 seconds and observe. Swirl again for the last 20 seconds and make your final observations. Expected Results Results may vary.
Discuss student observations and the possible identity of the unknown. Ask students: Are there any crystals that you could rule out as probably not the unknown? Based on their observations, students are most likely to eliminate sugar and Epsom salt as the unknown. You can test boiling point for example. You could try melting it over a Bunsen burner - the sugar will melt readily whereas the salt will not. You could also try dissolving the substance in alcohol.
The salt will dissolve only very slightly, but the sugar will dissolve readily. Sugar and salt are scientifically different because salt is sodium chloride NaCl were as sugar is C12H22O11 12carbon atoms per every 22 hydrogen and 12 carbons. Also sugar is sweet were as salt is salty. Salt and sugar have different chemical appearences and shapes.
Their taste is also different! Sugar and salt have different crystalline structures. Salt has a six sided shape, where sugar is more of a hexagonal prism with sharp edges. Table salt has a cube structure and table sugar has a hexagonal crystaline structure. You can tell the difference by the color salt is a little lighter but you cant tell that much.
Salt is a cystal with acid. Sugar isn't. If you have a microscope lying around then look at the characteristics and see which one you think it is. Table sugar is comprised of carbon, oxygen, and hydrogen, while table salt is made of sodium and chlorine. Additionally, table sugar is created with a covalent bond while table salt is created with an ionic bond.
The one without salt has less sodium. Salt typically comes in a round container about the size of a family can of chili beans and is labled salt. Sugar typically comes in a paper package and weighs about 5LBS and is labled sugar. So all you really have o do is read the packages. Table salt NaCl is a simple mineral, needed by the body in moderate amounts. Sugar C6H22O11 is a carbohydrate giving a sweet taste and quick energy. The experiment did not disappoint!
As with salt, sugar has radically different properties both physical and chemical than its constituent elements. This difference in properties, of constituent elements and compounds, is a central feature of chemical reactions.
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