Q: The separation of compounds on the basis of their solubilities in a given solvent is known as what? Read this paragraph and choose the correct option from the provided answers: Solubility may increase or decrease with temperature; the magnitude of this temperature dependence varies widely among compounds. Notice in particular the curves for NH4NO3 and CaCl2. The dissolution of ammonium nitrate in water is endothermic (Hsoln = +25.7 kJ/mol), whereas the dissolution of calcium chloride is exothermic (Hsoln = 68.2 kJ/mol), yet Figure 13.9 "Solubilities of Several Inorganic and Organic Solids in Water as a Function of Temperature" shows that the solubility of both compounds increases sharply with increasing temperature. In fact, the magnitudes of the changes in both enthalpy and entropy for dissolution are temperature dependent. Because the solubility of a compound is ultimately determined by relatively small differences between large numbers, there is generally no good way to predict how the solubility will vary with temperature. The variation of solubility with temperature has been measured for a wide range of compounds, and the results are published in many standard reference books. Chemists are often able to use this information to separate the components of a mixture byfractional crystallization, the separation of compounds on the basis of their solubilities in a given solvent. For example, if we have a mixture of 150 g of sodium acetate (CH3CO2Na) and 50 g of KBr, we can separate the two compounds by dissolving the mixture in 100 g of water at 80C and then cooling the solution slowly to 0C. According to the temperature curves in Figure 13.9 "Solubilities of Several Inorganic and Organic Solids in Water as a Function of Temperature", both compounds dissolve in water at 80C, and all 50 g of KBr remains in solution at 0C. Only about 36 g of CH3CO2Na are soluble in 100 g of water at 0C, however, so approximately 114 g (150 g 36 g) of Saylor URL: http://www. saylor. org/books. Choices: - nuclei crystallization - simplest crystallization - separate crystallization - fractional crystallization A:
fractional crystallization
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Q: Alterations that change chromosome structure are known as? Read this paragraph and choose the correct option from the provided answers: Chromosomal alterations are mutations that change chromosome structure. Choices: - lesions - traits - deformities - mutations A:
mutations
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Q: What disease occurs when cells in the breast grow out of control and form a tumor? Read this paragraph and choose the correct option from the provided answers: Breast cancer is the most common type of cancer in females. It occurs when cells in the breast grow out of control and form a tumor. Breast cancer is rare in teens but becomes more common as females get older. Regular screening is recommended for most women starting around age 40. If found early, breast cancer usually can be cured with surgery. Choices: - adult breast growth - muscle cancer - muscular cyst - breast cancer A:
breast cancer
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Q: A monosaccharide is the simplest carbohydrate and cannot be hydrolyzed to produce a smaller what? Read this paragraph and choose the correct option from the provided answers: A monosaccharide is the simplest carbohydrate and cannot be hydrolyzed to produce a smaller carbohydrate molecule. Disaccharides contain two monosaccharide units, and polysaccharides contain many monosaccharide units. Choices: - amino acid - glucose atom - quark - carbohydrate molecule A:
carbohydrate molecule
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