Water sugar dissolved

Every substance shows a more or less pronounced tendency to change. This was already stated by the Greek philosopher Heraclitus with the words Everything flows - Nothing stands stiU . For example, wet dishes, moist laundry, fresh bread, etc. dry in the air of a room, iron rusts when it is exposed to air and water, sugar dissolves in tea and so on. The perishing of foodstuffs in unopened cans and even pure chemicals in sealed bottles indicates that the cause for the ubiquitous change of substances is not an interaction between different reaction partners (as chemists believed in former times), but is an intrinsic property of each substance itself. 

In your laboratory work you will deal mostly with liquid solutions. Liquid solutions can be made by mixing two liquids (for example, alcohol and water), by dissolving a gas in a liquid (for example, carbon dioxide and water), or by dissolving a solid in a liquid (for example, sugar and water). The result is a homogeneous system containing more than one substance—a solution. In such a liquid, each component is diluted by the other component. In salt water, the salt... 

First we can investigate, qualitatively, the extent to which the solids dissolve in the liquids. By adding a small piece of each solid to a milliliter of liquid, we easily discover that sugar dissolves both in water and ethyl alcohol, sodium chloride dissolves readily in water but not in ethyl alcohol, and iodine does not dissolve much... 

Thus we find great variation among solutions. Iodine dissolves in ethyl alcohol, coloring the liquid brown, but does not dissolve readily in water. Sodium chloride does not dissolve readily in ethyl alcohol but does dissolve in water, forming a solution that conducts electric current. Sugar dissolves readily both in ethyl alcohol and in water, but neither solution conducts electric current. These differences are very important to the chemist, and variations in electrical conductivity are among the most important. We shall investigate electrical conductivity further but, first, we need to explore the electrical nature of matter. 

Sugar dissolves in water, but the resulting solution conducts electric current no better than does pure water. We conclude that when sugar dissolves, no charged particles result no ions are formed. Sugar must be quite different from sodium chloride. 

In view of the discussion of the factors that determine the rate of dissolving (Section 10-1.2), propose two methods for increasing the rate at which sugar dissolves in water. 

Sugar dissolves In water to give a solution that contains individual sugar molecules distributed uniformly among the water molecules. The aqueous sugar solution is stable and remains uniform indefinitely. Recall from Chapter 1 that a solution is a homogeneous mixture. On the microscopic scale, one microscopic portion of a solution looks the same as every other microscopic portion. 

Does lump sugar or granular sugar dissolve faster in water, all other factors being equal Explain. 

Sugar should be more soluble in ethanol than in octanol. Like dissolves like. Chemists know from experience that sugar dissolves well in water. Therefore, you expect sugar to dissolve best in solvents that are most similar to water. Because ethanol is more miscible with water than is octanol, you expect that ethanol has solvent properties (especially polarity) more like water than octanol does. 

Homogeneous means that the mixture has the same composition everywhere. When sugar dissolves in water, the mixture is homogeneous. A mixture that is not the same everywhere (such as orange juice, which has suspended solids) is heterogeneous. 

Figure 3-3 Separation of oligosaccharides by gel filtration. The sugars dissolved in distilled water were passed through a column of Sephadex G-25. The peaks contain (right to left) glucose, cellobiose, cellotriose, etc. From Flodin and Aspberg.64...

Put one cup of hot tap water in the two-cup measuring cup. Add one-half cup of sugar to the hot water. Stir the water with a spoon until the sugar dissolves. You can no longer see the sugar when it dissolves. 

Combine the sugar and I cup water in a small heavy-bottomed saucepan, and cook over high heat until the sugar dissolves and the... 

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