Answer:
A. Water and Sugar can be separated by evaporation and then crystallization
B. Mixture of Hexane and Octane can be separated by distillation
C. Solid Iodine, I₂ and NaCl can be separated by filtration and then evaporation
D. "Sharpie" permanent marking pen can be separated by chromatography
E. Nickel shavings and copper pellets can be separated by magnetic separation
Explanation:
A. A mixture of water and sugar can be separated by employing two separation techniques, evaporation and crystallization. First the sugar solution is heated to evaporate most of the water. When the solution becomes very saturated, it is allowed to cool and then the sugar molecules are obtained through crystallization induced by seeding or scratching the walls of the container.
B. A mixture of hexane (boiling point = 68 °C) and Octane (boiling point = 125 °C) can be separated by distillation due to their significant difference in boiling points.
The mixture is heated in a flask connected to a Liebig condenser. Hexane with the lower boiling point will distill over first and is collected. Afterwards, octane next distills over and is collected as well.
C. A mixture of solid iodine and NaCl can be seperated by first dissolving in water. Iodine being non- polar does not dissolve and is collected as a residue from filtration using a filter paper, while the NaCl solution is collected as the filtrate. The NaCl is recovered from solution by evaporating to dryness in an evaporating dish.
D. "Sharpie" permanent marking pen contains a mixture of dyes which can be separated by paper chromatography.
A drop of the marker ink is placed on a spot above the solvent level on the paper strip used for the separation. The paper strip is held vertically inside a jar containing a solvent which serves as the mobile phase. The jar is covered and the different dyes move along the paper which serves as the stationary phase, and is thus separated. The paper strip is removed from the jar when the ascending front of the solvent is approaching the top of the paper. The paper is dried and the various dyes can be identified by comparing the distance each has traveled with those of standards.
E. A mixture of nickel shavings and copper pellets can be separated by magnetic separation.
A magnet is brought near the mixture and the nickel shavings being magnetic is attracted to the magnet leaving copper pellets behind since copper is not magnetic.
