Answer:
(C) The recrystallization solvent should be nonvolatile.
Explanation:
Recrystallization is the separation technique which is used to purify the solid compounds in their crystal or amorphous form.
Some properties follow the recrystallization process as:
The solids are more soluble in hot solvent as compared to the solubility in the cold solvent.
The solvent must have lower boiling point and can be volatile easily.
The solvent should not react with the compound.
The impurities must be soluble in the cool solvent, so that only the pure product crystallizes.
Hence, Answer - C which is not an ideal characteristic.
This problem could be solved easily using the Henderson-Hasselbach equation used for preparing buffer solutions. The equation is written below:
pH = pKa + log[(salt/acid]
Where salt represents the molarity of salt (sodium lactate), while acid is the molarity of acid (lactic acid).
Moles of salt = 1 mol/L * 25 mL * 1 L/1000 mL = 0.025 moles salt
Moles of acid = 1 mol/L* 60 mL * 1 L/1000 mL = 0.06 moles acid
Total Volume = (25 mL + 60 mL)*(1 L/1000 mL) = 0.085 L
Molarity of salt = 0.025 mol/0.085 L = 0.29412 M
Molarity of acid = 0.06 mol/0.085 L = 0.70588 M
Thus,
pH = 3.86 + log(0.29412/0.70588)
pH = 3.48
Answer:
13.73g
Explanation:
mass of reactants = mass of products.
Mass reactants = 5.00 g + 10.00 g = 15.00 g
Mass products = 1.27g + mass of ammonia and water vapor
Mass of ammonia and water vapor
15.00g – 1.27 g = 13.73 g
Answer:
147.2g
Explanation:
The full solution can be found in the image attached. Graham's law was applied to the problem. The rate of diffusion of a gas is inversely proportional to its molar mass or vapour density. Molar mass= 2vapour density
