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physical chemistry

One problem that we will continue to face as the population of the earth steadily increases is fresh water. Even though there is an abundance of water on this planet, less than 5% of it can be used to sustain life. Therefore, new ways of purifying water are being developed. One of the best recent developments is using reverse osmosis. This process is being used to obtain fresh water from sea water by desalinization (salt removal). A membrane permeable to water but not to salt separates compartments containing sea water and fresh water. The normal flow of water, due to osmosis, from the fresh water to the sea water compartment is reversed by applying pressure to sea water campartment. For purposes of this problem, assume that the sea water is 3.0 weight percent NaCl. What is the minumum pressure (above atmospheric pressure) that must be supplied to cause reverse osmosis to occur at 25 degrees Celsius.

A dilute aqueous solution NaOH is heated to boiling. The boiling point of this solution is greater than 100.01 degrees Celsius at 760 torr. As som eof the water is boiled off, the boiling point of the resultant solution is checked again and it is found to be less than the previous boiling point (i. e., less than 100.01 degrees Celsius). Explain all these observations as fully as possible. Also, determine the original molal concentration of the NaOH. kb for water is 0.512 degrees Celsius/molal. The boiling point of the original solution is actually 100.01024 degrees Celsius at 760 torr.

Both potassium chloride (KCL) and potassium hydroxide (KOH) are very soluble in water. However, as one increases the temperature of the solution, KCL becomes more soluble and KOH becomes less soluble. Explain

The alkaline earth metal beryllium, Be, is very small and forms covalent compounds instead of ionic compounds. Knowing this, what type of solids would BeFCl and BeCl2 form and which would have the higher melting point? Please explain the answer.

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It provides detailed explanations of a couple of physical chemistry questions, such as the solubility of KCl and KOH, melting point of BeFCl and BeCl2, and minimum pressure for reverse osmosis process. The solution is detailed and has a '5/5' rating.

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