Concept OF Solubility AND Miscibility Lab Report PDF

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Concept OF Solubility AND Miscibility...

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ABSTRACT : The objectives are to examine some of the terms and concepts associated with solutions. Next, to investigate solute and solvent interaction. Then, to learn to make inferences about the nature of substance , based on their solubility or miscibility. For solubility of solid, distilled water, ethanol and hexane had been used as solvent. The mass solute that used is sodium chloride, oxalic acid and paraffin. Some of the mass solute dissolve in the solvent. For miscibility of liquids the same solvent had been used but this time 2 ml of cooking oil had been add to each solvent. Different result have been observe in 3 different solvent. The relative solubility of a solute had been observe by mixing methylene chloride and water. Then, 2 drop of iodine had been add to observe the changes in colour for the aqueous. In this experiment, we can conclude that the polar solute will dissolve in polar solvent or vice versa. Polar solvent is miscible with polar solvent.

INTRODUCTION : This experiment has been carried to study about solubility and miscibility between solute and solvent. Solubility refers to the ability of the given mass solute dissolve in a given mass solvent. It refers to the relation between solute and solvent. Miscibility refers to the ability of one liquid to dissolve in another one liquid, forming a mixture of liquid.

LITERATURE REVIEW : Solids that dissolve in liquids are soluble. Those that do not dissolve are insoluble. Liquids that mix with other liquids are miscible. Those that do not dissolve are immiscible. Polar solvents dissolve polar solutes. Non-polar solvents dissolve non-polar solutes.

METHODOLOGY : A. Solid in Liquids Label nine test tube as 1 to 9

Weight 1.0 g paraffin and put in into test tube 3, 6 and 9 each. Repeat step 6

Fill test tube 1, 2 and 3 with distilled

Weight 1.0 g oxalic acid and put it into

water ( approximately ¼ full )

test tube 2, 5 and 8 each. Repeat step 6

Fill test tube 4, 5 and 6 with ethanol

Shake the mixture vigorously for about

( approximately ¼ full )

30 seconds. Observe whether the solute dissolve in the solution or not.

Fill 7, 8, and 9 with hexane

Weigh 1.0 g sodium chloride and put it into

( approximately ¼ full )

test tube 1,4,and 7 each.

B. Misibility of Liquids Add water, ethanol and hexane to different test tube (approximately ¼ full)

Add 1 mL cooking oil to each of the 3 test tube.

Observation had been record in

Froth gently to mix the aqueous.

the table

C. The Relative Solubility of a Solute in Two Solvents 2 ml methylene chloride mix with

The relative position of each liquid

4 ml water

had been observed by noting the volume of each liquid

2 drops of an iodine had been added

The mixture had been shake for five

to the test tube and the colour of

seconds and the observation was

each layer and their intensities was

recorded

noted

DATA TABULATION :

Solvent

Solute Sodium chloride

Oxalic acid

Paraffin

Water

1 Dissolve

2 Dissolve

3 Do not dissolve

Ethanol

4 Do not dissolve

5 Dissolve

6 Do not dissolve

Hexane

7 Do not dissolve

8 Do not dissolve

9 Do not dissolve

TABLE 1

Based on the table 1 when water used as a solvent, the solutes such as sodium chloride and oxalic acid were dissolved completely while the other solute like paraffin added to water it do not dissolve. After that, the same method had been carried by using ethanol, but this time it dissolve with oxalic acid only while sodium chloride and paraffin do not dissolve .When sodium chloride, oxalic acid and paraffin been put into hexane, all of the solute did no dissolve.

Solvent

Observations

Water

Water is at the bottom layer while cooking oil at the upper layer

Ethanol

Cooking oil is in the bottom layer while ethanol on the upper layer

Hexane

Oil dissolve in hexane and solution become yellowish

TABLE 2 Based on table 2, when water mix with cooking oil in the test tube, a double layer liquid was formed which is the water was more denser than cooking oil. On the other hand, when ethanol mix with cooking oil, there were also a double layer liquid has formed. But this time, cooking oil was more denser than ethanol. When hexane mix with cooking oil, it formed a yellowish solution.

RESULT : For experiment C when when methylene chloride and 4 ml water mix, double layer aqueous formed. Methylene chloride was gather on the bottom of the test tube while water was on the upper side of the test tube. Then 2 drops of an iodine put into the solution after that, the test tube had been shaked for 20 seconds. There is a changes in the colour. For the aqueous layer turned to yellowish and for the methylene chloride layer turned to pink.

DISCUSSION & EXERCISE : 1. In the like dissolve like rule, it is clearly state that polar solute will dissolve in the polar solvent and vice versa. Therefore, oxalic acid will dissolve in the ethanol while the paraffin will dissolve in the hexane. 2. Cooking oil is a nonpolar molecule because it does not dissolve in water and ethanol but dissolve in hexane which is a nonpolar solvent. This phenomenon can be explained by using the dispersion force. The dispersion force in hexane readily substitute for the dispersion force in the oil. For a solution formed, the attraction force between hexane and cooking oil is comparable in magnitude to the attraction force between cooking oil molecule and hexane molecule.

Exercise 1.The differences between miscible and soluble Miscible is when two substances completely mix with each other to form homogeneous solution. While soluble is when one substance completely dissolves in another substance. 2.Characterize these compounds as soluble or insoluble in water

a) CaCO3

law of

Insoluble - No it is definately insoluble in water. it is a substance that defys the polar and ionic compounds being soluble in water. ->

b) ZnSO4 -> Soluble - Zinc sulfate is soluble in water because all sulfates are soluble in water. . c) Hg(NO3)2 -> Soluble – Substances that consist ion nitrat always solube. d NH4ClO4 -> Soluble – Salts containing the ammonium ion (NH4+) are also soluble.

3. While working in a machine shop you split a spot of grease on your shirt sleeve. In order to remove it, ehst would you use as a solvent with which to wash the spot? Water, ethanol or hexane? Explain why? Hexanes will dissolve the large, non-volatile greasy molecules which form the stain (hexanes are non-polar, i.e. oily, and the oily molecules from the stain will dissolve in it, something they will not do well in water--hence the difficulty in getting them out of clothing). Once the grease stain is dissolved, and washed away in the hexane, any hexane molecules left in the clothing will evaporate, and will thus not stain the cloths themselves. I f t heywer enotl i ghtenought oev apor at et heywoul dbej us tasdi ffic ul tt ogetoutast heor i gi nal s t ai n.

CONCLUSION : In this experiment, the polar solvent will solute in polar solvent. It is same for both solubility and miscibility. The difference was only solubility was between solid substances and a liquid. For miscibility it was a mixture of two liquids and become a solution. For recommendation, this experiment should be conduct away from fire sources because hexane and ethanol is flammable and volatile.

REFERENCE :

Book : - O. Olabisi, L. M. Robenson, and M. T. Shaw, Polymer-Polymer Miscibility, Academic Press, Inc, New York, !969. - M. H. Coleman, J. E. Graf and P. C. Painter, Specific Interactions and the Miscibility of Polymer Blends, Technomic Publishing Co., Inc., Lancaster, Pa., 1991. - I. Prigogine, The Molecular Theory of Solutions, North Holland Publishing Co., Amsterdam, 1957. Website : https://www.google.com.my/? gws_rd=cr&ei=7fIiVJaXLoK2uAS88oHICQ#q=miscibility+and+solubility...