A colloidal solution of gold nanoparticles is prepared by reduction of . Which of the following methods is MOST EFFECTIVE for purifying this solution from excess reactants and small ionic byproducts?
Filtration
Centrifugation
Dialysis
Evaporation
Related Questions
A 1 molal aqueous solution contains 0.5 moles of solute. What is the mass of the solvent (water) in kilograms?
0.5 kg
1 kg
2 kg
1.5 kg
A mixture of two volatile liquids A and B shows a negative deviation from Raoult's law. Which of the following statements is INCORRECT regarding this mixture?
The enthalpy of mixing is negative.
The volume of mixing is negative.
The boiling point of the mixture is lower than that predicted by Raoult's law.
The intermolecular forces between A and B are stronger than the A-A and B-B interactions.
Which of the following describes a 0.5 molal solution?
0.5 moles of solute in 1 kg of solvent
1 mole of solute in 0.5 kg of solvent
0.5 moles of solute in 0.5 kg of solvent
1 mole of solute in 1 kg of solvent
A solution is prepared by dissolving 2.5g of a non-volatile solute in 100g of water. The vapor pressure of the solution is found to be 22.87 Torr at . If the vapor pressure of pure water is 23.76 Torr at the same temperature, what is the molar mass of the solute (in g/mol)?
60
120
30
90
Which of these is the correct formula for calculating molality?
Moles of solute / Liters of solution
Moles of solute / Kilograms of solvent
Grams of solute / Liters of solution
Grams of solute / Kilograms of solvent
A solution is prepared by dissolving 10 g of sucrose () in 200 g of water. What is the mole fraction of sucrose?
0.0026
0.0292
0.0500
0.997
A 0.5 molal aqueous solution of urea () is prepared. What is the mole fraction of urea?
0.0089
0.0090
0.50
0.99
A solution is prepared by dissolving 10 g of glucose in 190 g of water. What is the mass percentage of glucose in the solution?
5%
10%
2%
95%
What is the molality of a solution where the mole fraction of the solute is 0.02 and the solvent is water?
1.13 m
0.02 m
0.98 m
55.51 m
