15.0 grams of NH4Cl is added to 80.0 grams of water in a calorimeter cup. The temperature of the solution goes from an initial temp of 22.0 ºC to 17.5 ºC. What is the change in heat in kcal/mol? Be sure to include a + or - sign.

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Seltzer water is created by placing water under pressure with carbon dioxide gas. which of the following statements best describe seltzer water: a. the solution will be slightly acidic b. the solution will be slightly basic. the solution will be strongly acidic. d. the solution will be strongly basic. e. the solution will be neutral

Assuming complete dissociation of the solute, how many grams of kno3 must be added to 275 ml of water to produce a solution that freezes at -14.5 c? the freezing point for pure water is 0.0 c and k_f is equal to 1.86 c/m