How many grams of the solute are required to prepare 25mL of 1.2 M potassium nitrate solution?

. For quick preparation of a cup of hot chocolate in a cafeteria, cocoa powder and sugar

are added in a cup of water and the solution is heated by direct steam injection. If the

initial temperature of all the ingredients is 15 ℃, the final temperature is 95℃, the mass

of the solution is 150g initially, and the heat capacity of the solution is 3.8 kJ/kg ℃,

calculate how much saturated steam at 110 ℃ will be used. State your assumptions.

a magnesium hydroxide solution is prepared by adding 10.00 g of magnesium hydroxide to a volumetric flask and bringing the final volume to 1.00 l by adding water buffered such that the ph will remain at 7.0. what is the concentration of magnesium in this solution? (assume standard pressure and temperature and the ionic strength is negligible)

Suppose 10 mg of L-deprenyl is diluted in 10 ml water (density 1.0g/ml) and the solution is to be used in the sugary solution approach. What is the mole fraction of the drug? What is the molarity of the drug (mol/L?