Mass transfer - humid air is at 40ºc with 20% relative humidity. a.) what is the wet bulb temperature? b.) if the air is in a 5 l flask and cooled until it condenses, what temperature does condensation occur? c.) what is the mass of dry air, water, and humid air in the flask? d.) what is the enthalpy change for this cooling (in j)? e.) if the flask was cooled further, to 4ºc, what fraction of the water in the humid air will condense?

Astudent is given a sample of a blue copper sulfate hydrate. he weighs the sample in a dry covered porcelain crucible and got a mass of 23.875 g for the crucible, lid, and sample. the mass of the empty crucible and lid was found earlier to be 22.652 g. he then heats the crucible to expel the water of hydration, keeping the crucible at red heat for 10 minutes with the lid slightly ajar. on colling, he finds the mass of crucible, lid, and contents to be 23.403 g. the sample was changed in the process to very light clue anhydrous cuso4. if there are again 100.0 g of hydrate, how many grams of cuso4 are in it? how many moles of cuso4? (hint: molar mass of cuso4 = 159.6 g / mole. what per cent of the hydrate is cuso4? you may convert the mass of cuso4 to moles.)

Aglow stick contains a glass vial with chemicals. when the glow stick is bent, the vial breaks and the chemicals react to produce a glow. a science student observes that a glow stick kept in the freezer glows for a longer duration than a glow stick kept at room temperature. what conclusion can be drawn based on the observation? be sure to note the outcome and test variables in the conclusion.

Calculate the percent composition by mass of each element in al(oh)3. use at least three significant figures.