Models are often used in Science to assist our understanding of certain concepts or help to explain observations. Below are models for the three solvents used in this experiment.
a) Identify each solvent. (3)
b) Label if they polar, non-polar, or the polar and non-polar ends. (3)
c) By referring to the models, explain why each solvent did or didn’t dissolve the substances tested. (Word count 75 – 150 words for each) (13)
Model A: Ethanol- non polar & polar Explanation:
Sugar- Sugar is a polar (hydrophilic, water loving) molecule, whereas ethanol is a non-polar (hydrophobic, water hating) molecule. Sugar emulsifiers within the ethanol (alcohol solvent). They have the same properties as water; therefore the sugar will dissolve within the ethanol.
Salt- Salt is a polar molecule whereas ethanol is non- polar. Salt does not dissolve within alcohol because of the hydrogen bonds that are moulded when the solution is formed. (BLURT IT,…show more content… Sugar emulsifies within water causing a solution to form.
Salt: Is also a polar molecule therefor with dissolve within the water because it is also a hydrophilic, water loving molecule.
Kerosene: is a non-polar molecule therefor will not dissolve within the water, as water is a polar molecule therefor they have different emulsifying structures and will not show solubility.
Salicylic Acid: Is a non-polar molecule and will not show solubility within water because of its non-polar interactions.
Vaseline- Is a non-polar molecule and will not dissolve within water because of its oil content.
Margarine- Is also a non-polar molecule and will not dissolve within water as it has a high fat and oil content.
Question 2 (12 marks)
a) Outline the steps undertaken in this investigation to minimize wastage of resources. Justify the steps