Describe the circumstances in which the following processes could be used to separate the components of a mixture.
-sublimation
-crystallization
-evaporation of a solvent from a solution
-dissolving of an impure substance in a solvent
-sublimation: If you have a mixture where one component can undergo sublimation (turn from solid to gas directly), you can separate it from the other components that don't sublimate. So, imagine you have a mixture of clown makeup and cotton candy. If you heat it up and the clown makeup sublimes into a gas, you can say: "Poof! Goodbye clown makeup, hello cotton candy!"
-crystallization: Let's say you have a mixture of sugar and salt. If you dissolve this mixture in water and then cool it down, the sugar will begin to crystallize out of the solution, leaving behind the salt. It's like magic! The sugar says, "I'm so sweet, I'll just turn into crystals and leave the salty fellow behind!"
-evaporation of a solvent from a solution: This process is like when you leave a glass of water out in the sun, and most of it disappears. If you have a mixture of saltwater, you can heat it up and let the water evaporate, leaving the salt behind. The water goes, "I'm outta here!" and the salt waves, saying, "Sea ya later!"
-dissolving of an impure substance in a solvent: Let's say you have a spoonful of dirt mixed in with some water. When you stir it, the dirt dissolves into the water, creating a muddy liquid. But fear not! By using a filter, you can separate the dirt particles from the water. The dirt cries, "I can't handle this separation anxiety!" and the water smiles, saying, "I'm all clean now!"
1. Sublimation: Sublimation is a process used to separate a mixture when one component can undergo sublimation, which is the direct transition from a solid to a gas without passing through the liquid phase. This technique is applicable when the desired component of a mixture can sublime, while the other components remain as solids. By subjecting the mixture to conditions that induce sublimation, the volatile component can be collected as a gas, leaving behind the non-volatile components.
2. Crystallization: Crystallization is a process used for separating components based on differences in their solubilities. When a mixture contains a solid component that is more soluble in a particular solvent at higher temperatures but less soluble at lower temperatures, crystallization can be used. By dissolving the mixture in a hot solvent and gradually cooling it, the solubility of the solid component decreases, causing it to crystallize out of the solution. The crystals can then be separated from the remaining liquid by filtration or other separation methods.
3. Evaporation of a solvent from a solution: This process is used when the desired component is dissolved in a solvent and needs to be recovered. By heating the solution, the solvent can be evaporated, leaving behind the solid or dissolved component. The evaporated solvent can be condensed and collected, while the remaining solid or dissolved component can be retrieved.
4. Dissolving of an impure substance in a solvent: This process involves dissolving an impure substance in a suitable solvent to selectively separate the desired component from the impurities. The impurities may have different solubilities in the solvent compared to the desired component. By dissolving the mixture in a solvent and manipulating factors such as temperature or concentration, the impurities can be left behind as a residue, while the desired component remains dissolved. The remaining solid or liquid can then be separated from the impurities using techniques such as filtration or decantation.
1. Sublimation: Sublimation is a process in which a solid substance directly converts into a vapor without going through the liquid phase. It can be used to separate components when one of the substances in the mixture has the property of sublimation, while the other components do not. Under specific conditions of temperature and pressure, the sublimable substance will vaporize, leaving behind the non-sublimable components. This process is commonly used to purify substances like iodine, napthalene, and dry ice (solid carbon dioxide).
To carry out sublimation, the mixture is heated under controlled conditions, allowing the sublimable substance to vaporize. The vapor is then collected and cooled, causing it to condense back into solid form, which can be collected separately.
2. Crystallization: Crystallization is the process of forming solid crystals from a solution or a melt. It is based on the different solubilities of components in a mixture. If one of the substances in the mixture is more soluble than the others, it can be selectively separated by crystallization.
To separate components using crystallization, the mixture is dissolved in a suitable solvent at an elevated temperature. When the solution is slowly cooled or left undisturbed, the solubility of the least soluble component decreases, leading to the formation of crystals. These crystals can then be separated through methods such as filtration or centrifugation.
3. Evaporation of a solvent from a solution: This process is used when the mixture consists of a solute dissolved in a solvent, and the goal is to obtain the solute in its solid form. By evaporating the solvent, the solute is left behind as a solid residue.
To separate components through evaporation, the mixture is heated to a temperature at which the solvent has a lower boiling point than the solute. As the solvent vaporizes, it can be collected separately, leaving the solute behind. The collected vapor can further be condensed to recover the solvent for reuse.
4. Dissolving of an impure substance in a solvent: This process is used when the mixture contains an impure substance that can be dissolved in a solvent. By dissolving the impure substance, other insoluble components can be separated.
To carry out separation using this method, the impure mixture is added to a suitable solvent, in which one of the substances is soluble. The mixture is then agitated or heated to enhance the dissolution process. Once the impure substance is dissolved, the insoluble components can be removed by techniques like filtration or decantation. Finally, the solvent can be evaporated to obtain the pure substance.
This is a lot of writing. I shall be happy to critique your thoughts. If you don't know the process in each, look on google, read your text/notes, ask here and explain what you don't understand.
Here is the answers
1. C
2. B
3. A
4. D
5. B
100% I got the answers just now because I had failed it. So now you guys know the answers. Hope this helps (: :)