GENERAL CHEMISTRY
CHM02/G203
Experiment 2: Effect of Nature of Solute and Solvent on Solubility
Score: 2016144102
PDS: Front Page:
Group # 5
Discussion: Conclusion: Total:
DISCUSSION: A solution is a homogeneous mixture. It is composed of two components: the solute and the solvent. The solute has lesser amount and to be dissolved by the solvent. The solvent has a greater amount than the solute that makes the solute dissolved. In this experiment, specific solutions will be tested for their solubility. In order for the group to test the solubility of a solution of solid in liquid, they have to weigh 0.15g of each sodium chloride and naphthalene. Placed each solid in separate micro test tubes. Then add 10 drops of distilled water to each micro test tube. After doing so, a group member stir and the rest of the members as well a s the one stirring, observed if the solids are soluble in water. After the process has been finished, the group repeated the procedure but now using the kerosene as a solvent. A. Solubility of Solid in Liquid Solute
Water (H2O)
Kerosene
Sodium chloride (NaCl)
soluble
insoluble
Naphthalene(C 10H8)
insoluble
soluble
Based on the results above, sodium chloride is soluble in water. When NaCl is added to water, Na+ is attracted to the oxygen of the water, while Cl- is attracted to the hydrogens of the water(Hydrogen bonding of the Intermolecular forces). This is the reason why NaCl dissolves in the solvent water. It was seen that NaCl is not soluble to the solvent kerosene, this is because NaCl is an ionic molecule, there is a difference between Sodium and Chlorine as it comes to electronegativity, due to the differences in electronegativity this gives po larity to both elements. Making Sodium chloride a polar molecule. Generally polar molecules will dissolve in polar solvents and insoluble in non-polar solvents. Non-polar molecules will dissolve in non-polar solvents and insoluble in polar solvents. As sodium ch loride is polar molecule it will be soluble in polar solvents like water and insoluble in kerosene (as it is non-polar solvent). In addition to the results above, it is shown that C 10H8 is insoluble in water and soluble in kerosene because
naphthalene is a non-polar molecule making it insoluble in water(polar solvent) and soluble in kerosene(non-polar solvent). In order for the group to test the solubility of liquid in liquid, they have to place 10 drops of ethyl alcohol and coconut oil in separate micro test tube. Same as the first process, somebody stirred the solution while the others observed the happenings in the solution if the liquids are miscible in water or kerosene. B. Solubility of Liquid in another Liquid Solute
Water (H2O)
Kerosene
Ethyl alcohol(C2H6O)
miscible
immiscible
Coconut oil
immiscible
miscible
Based on the results shown above, it is stated that C2H6O is miscible in water and immiscible in kerosene. Water is known to be polar so it attracts the OH group, meanwhile Carbon chain is non-polar that is why it repelled. Alcohol solubility is determined by which is stronger in both forces, because if OH attraction is strong, ethanol is completely miscible. Ethanol is a polar molecule that is why it is repelling to the miscibility of the kerosene which is a non-polar molecule. Same goes to the interaction of H2O and coconut oil, as we all know that oil has a lesser density than water, for it will not b e soluble/miscible to the solvent water. As for the kerosene and coconut oil, it is miscible because coconut oil and kerosene is considered a jet fuel, both being related to fuel, it is miscible as it can be an alternative fuel. Considering the polarity of both substances, both are non-polar which makes the coconut oil solute dissolves in solvent kerosene. C. Solubility of Gas in Liquid The group is required to have a softdrinks can. For the solubility to be observed, the group opened the can of softdrinks. The solubility of gas is directly proportional to pressure, upon opening the softdrinks can, bubbles will be visible and liquid will rise. Due to the Carbon dioxide being released from the liquid because the pressure inside tha can dropped due to it being opened.
CONCLUSION: It is clearly stated in the experiment that the polarity of the molecule has an effect to the solubility of the substances. A polar molecule solute is soluble/miscible in another polar molecule solvent. A non-polar molecule solute is s oluble/miscible in another non-polar solvent, regardless of the state if it was solid in solid or liquid in liquid. In simpler terms, solute and solvent dissolved to what they have the same polarity as the polarity greatly contributes to the solubility.
