Rogationist CollegeHigh School Department

SY 2009-2010

SOME FACTORS THAT AFFECTS SOLUBILITY

By: Pillerva, Allan B.Quilo, Lucille Mae T.

Sunga, Jerold Chester D.Toledo, Kristin Elisha P.

Tolosa, Aila Arielle S.III – ST. GREGORY

ABSTRACT

This experiment aims for what was to determine the effects of temperature and nature of the solute and solvent on the solubility of a substance. The effect of temperature on solubility was determined using sucrose, water and alcohol lamp. Several numbers of grams of sucrose was added to water and was heated in 50° C. Nature of the solute and solvent on the solubility of a substance determined how the nature of solute and solvent affects solubility using salt, sugar and iodine as the solutes and water, ethyl alcohol and isopropyl as the solvents. Solute was added to the solvents (one solvent on one solute). The students thought that with the nature of the solute and solvent, the higher the polarity of the solvent, the higher the solubility of the solute while with temperature, the higher the heat of the solvent, the higher the solubility of the solute.

INTRODUCTION

In our daily lives we may notice many substances that dissolves in certain liquids; these dissolving changes have two factors that affect solubility, effects of temperature and the nature of solute and solvent on solubility. Effects of temperature refer to how the temperature affects the dissolving of the solute from the solvent. The nature of solute and solvent on solubility refers to some solutes doesn’t dissolves totally to some solvents in terms of solubility and polar events. The maximum amount of solute that can dissolve in a given amount of solvent at a given temperature to form a saturated solution is called solubility. Polar solvent dissolves polar solute while a non polar solvent dissolves non polar solute.

The objective of this activity is to determine the effects of temperature and the nature of solute and solvent on solubility. In this experiment we can see the how a solute dissolves through a certain process and affects the factor of solubility.

METHODS AND PROCEDURE

A.) EFFECTS OF TEMPERATURE

A 10mL of distilled water was poured in a beaker and its temperature was measured and recorded. 2 grams of sugar (C12H22011) was added to water (H20). While the solution is being added with the glass rod, the portion of sugar was being added until no sugar was saturated. The total amount of sugar added was recorded. At 50° C, the beaker with the saturated sugar was heated and stirred with the stirring rod and the flame has been regulated so that the flame or the heat of the alcohol lamp will remain the same and I continuously added 2 gram portions of sugar until no more sugar can be dissolved. The beaker was left to a cool room and was observed afterwards.

B.) Nature of Solute and Solvent

The test tubes were labeled from 1 to 3. 0.1g each salt (NaCl) had been put to test tube 1. Sugar (C12H22011) of the same amount as the salt had been put to test tube 2 and Iodine (I2) of the same amount as the salt and sugar had been put to test tube 3. 3mL of distilled water was added to each test tube. To allow the solids to dissolve the test tube was shaken. Each test tube was observed and noted whether it is soluble, slightly soluble and insoluble in water, the first 3 steps was repeated but this time ethyl alcohol (C2H5OH) and Isopropyl alcohol ((CH3)2CO). The observation was recorded.

RESULTS AND ANALYSIS

A. EFFECTS OF TEMPERATURE

1.) Initial temperature of distilled water t1 =28° C2.) Mass of sugar (C12H22O11) m1 dissolved at t2 =16g3.) Additional mass of m2 sugar dissolved at t2 = 50°C = 2g4.) Total mass of sugar ( m1 + m2) dissolved at t2 = 18g5.) Observations on cooled sugar solution: other portions of sugar are seen

afterwards.

Sugar (C12H22O11) was gradually added to water (H20) in several portions so that it is easy to know how many grams of sugar can be dissolved in a 10 mL water at normal temperature. Furthermore, when water was heated it was easier to dissolve sugar than on the initial temperature. Also sugar can be dissolved in heated water more than at its normal temperature.

B. NATURE OF SOLVENT AND SOLUTE

Solute Solvent

Water(H20)

Ethyl Alcohol(C2H5OH)

Isopropyl Alcohol ((CH3)2CO)

Salt (NaCl) Soluble Insoluble Slightly Soluble

Sugar (C12H22011) Soluble Insoluble Slightly SolubleIodine (I2) Insoluble Slightly Soluble Insoluble

Based on the table above, Salt (NaCl) and sugar (C12H22011) dissolves in water (H20) while Iodine (I2) did not but on the other solvents, Ethyl Alcohol (C2H5OH) and Isopropyl Alcohol ((CH3)2CO), salt and sugar slightly dissolves or it doesn’t dissolve at all same as on Iodine. While the polar solvents, water and isopropyl alcohol dissolves polar solutes such as salt and sugar, nonpolar solvents like ethyl alcohol dissolves nonpolar solutes like Iodine.

CONCLUSION

Based on the experiment one of the factors that affects solubility is temperature. When the solvent is at a high temperature it is easier for the solute to de dissolve but when the solvent is in a normal temperature it takes a longer time for the solute to be dissolved. As for the other experiment, some solutes dissolves on polar solvents while they are insoluble in non-polar and vice versa on other solutes. “Like dissolves like” means that when a solute is not compatible with each other they will not react and when they are compatible to solute it helps each other to dissolve easily.

REFERENCES

Pili, Adora S., 2002, Science in Today’s World Chemistry Textbook III. Sibs Publishing House

Pili, Adora S., 2002, Science in Today's World Chemistry Laboratory Manual III. Sibs Publishing House.