Velammal New Gen School Chemistry Project 2024-2025 PDF

VELAMMAL NEW GEN SCHOOL NEDUNGUNDRAM SENIOR SCHOOL CERTIFICATE EXAMINATION CHEMISTRY (043) PROJECT REPORT ON STUDY OF RATE OF EVAPORATION OF DIFFERENT LIQUIDS (2024 – 2025) NAME: CLASS: XII...

VELAMMAL NEW GEN SCHOOL NEDUNGUNDRAM SENIOR SCHOOL CERTIFICATE EXAMINATION CHEMISTRY (043) PROJECT REPORT ON STUDY OF RATE OF EVAPORATION OF DIFFERENT LIQUIDS (2024 – 2025) NAME: CLASS: XII REG.NO:  BONAFIDE CERTIFICATE This is to certify that this CHEMISTRY Project on the topic STUDY OF RATE OF EVAPORATION OF DIFFERENT LIQUIDS has been successfully completed by of class XII (CHEMISTRY– 043), Roll.no …………………. at Velammal New-Gen School, Nedungundram for the partial fulfilment of this project as a part of Senior School Certificate Examination-CBSE, New Delhi for the academic Year 2024– 2025. Date: ……………. Signature of Principal Signature of the Guide Submitted for SSCE 2024-2025, CHEMISTRY Practical examination on …………………. Signature of the Signature of the Internal Examiner External Examiner  ACKNOWLEDGEMENT Apart from the efforts taken by me, the success of the project depends largely on the encouragement and guidelines of many others. I take this opportunity to express my gratitude to the people who have been instrumental in the successful completion of this project. I express deep sense of gratitude to almighty God for giving me the strength to complete the project successfully. I express my heartfelt gratitude to my parents for the constant encouragement while carrying out this project. I express my deep sense of gratitude to our honorable Principal HILDA MABEL R, who has been continuously motivating and extending a helping hand to us. My sincere thanks to Ms. SUGAIRA BANU a guide, mentor, above all a friend, who critically reviewed my project and guided me during the implementation of the project. The guidance and support received from all the members who contributed, was vital for the success of the project. I am grateful for their constant support and help. NAME: CLASS:  INDEX 1. OBJECTIVE 2. INTRODUCTION 3. FACTORS AFFECTING RATE OF EVAPORATION 4. APPLICATIONS OF EVAPORATION 5. USES OF DIFFERENT LIQUIDS 6. EXPERIMENT-1 7. EXPERIMENT-2 8. EXPERIMENT-3 9. EXPERIMENT-4 10. EVAPORATION IN DAILY LIFE 11. CONCLUSION 12. BIBLIOGRAPHY  OBJECTIVE To study the effects of various factors on evaporation of liquids and hence find out the factors affecting rate of evaporation. The factors to be tested are : 1. Nature of liquid 2. Surface Area of Liquid 3. Temperature 4. Environmental factors 5  INTRODUCTION There are many processes in life that take place on a daily basis. Some are so common we don’t even notice them happening every day. One such process is that of evaporation. We all have studied about it in science and it sure seems interesting. Similarly, one may often wonder what good it does to us or the planet. It is a very essential part of the water cycle and takes place continually throughout nature. Evaporation is a process in which water changes from a liquid state to a gaseous state. While the boiling temperature of the water is 100 degrees Celsius, it evaporates at 0 degrees Celsius very slowly. The rate of evaporation keeps increasing as and when the temperature increases. Evaporation happens when the liquid turns into a gas. The process begins when the molecules of the liquid get energy in the form of heat. They then turn into a vapour after this gaining of energy. One more important thing to understand is that this process happens only on the surface of the liquid and not throughout the whole body or volume. During evaporation, the pressure of the surrounding atmosphere is higher than that of the vapour. On the contrary, condensation is the opposite of this process. Examples of Evaporation : 1. Rain cycle 2. Strenuous activities ( when body produces sweat ) 6 Evaporation of liquid can be explained in terms of kinetic molecular model. Although there are strong intermolecular attractive forces which hold the molecules of liquid close together,, the molecules having sufficient kinetic energy can escape into gas if such molecules happen to come near the surface. In a sample liquid all the molecules do not have same kinetic energy. There is small fraction of molecules which have enough kinetic energy to overcome the attractive forces and escape into gas phase. The figure below shows the distribution of a molecule. If ' Emin' corresponds to minimum kinetic energy required to overcome the attractive forces and escape, the shaded area in the graph represents the molecules who have enough kinetic energy to escape Evaporation causes cooling. this is due to the fact that high energy molecules causing the high temperature of the liquid escape The vessel through evaporation. If the temperature is kept constant the remaining liquid will have the same distribution of molecular Kinetic energies and high energy molecules will keep on escaping into gas phase. If the liquid is taken in open vessel, evaporation will take place until whole liquid is evaporated. 7  FACTORS AFFECTING RATE OF EVAPORATION 1. RATE OF EVAPORATION: A liquid’s surface area and temperature affect its rate of evaporation. Evaporation rate also depends upon the type of liquids, since liquids are made up of different molecules and differ in the amount of abstraction that exists between the molecules. TEMPERATURE: It is also affected by temperature. As the temperature of the air is increased its capacity to hold moisture also increases. Any increase in air temperature raises the temperature of liquid at the evaporation source which means that more energy is available to the liquid to a gaseous state. Hence evaporation is directly proportional to the temperature of evaporating surface. The warmer the evaporating surface, higher the rate of evaporation. AIR-PRESSURE: Evaporation is also affected by the atmospheric pressure exerted on the evaporating surface. Lower pressure on the open surface of the liquid results in a higher rate of evaporation. RELATIVE HUMIDITY: The rate of evaporation is closely related to the relative humidity of the air. Since the moisture holding capacity of air at a given temperature is limited, 8 drier air evaporates more liquid than moist air. In other words, the higher the vapour pressure, the lower the rate of evaporation. It is a common experience that evaporation is greater in summer and at mid-day than in winter and at night. 2. SURFACE AREA AND TEMPERATURE: Because molecules or atoms evaporate from a liquid’s surface area allows more molecules or atoms to leave the liquid, and evaporation occurs more quickly. For example, the same amount of water will evaporate faster if spilled on a table than if it is left in the cup. Higher temperature also increases the rate of evaporation. At higher temperature molecules or atoms have a higher average speed. And more particles can break free on liquid’s surface. 3. INTERMOLECULAR FORCES: Most liquids are made up of mutual attraction among different molecules, which helps explain why some liquids evaporate faster than others. Attractions between molecules arise because molecules typically have regions that carry a slight positive charge. These regions of electric charges are created because some tons in a molecule are often more electronegative than the hydrogen atoms. Intermolecular attractions affect the rate of evaporation of a liquid because 9 strong intermolecular attraction holds the molecule in a liquid more tightly As a result, liquids with strong intermolecular attractions evaporate more slowly than those strong intermolecular forces. This is the reason why gasoline evaporates faster than water. The stronger the forces keeping the molecules together in the liquid state the more energy that must be input to evaporate them. 10 EXPERIMENT-1 AIM- To compare the rates of evaporation of a) Water b) Acetone REQUIREMENTS-Two petri dishes, 5ml syringe, stopwatch, water and acetone. PROCEDURE- I. Using the syringe, suck 5ml of the water and acetone separately and then pour them into two petri dishes. II. Put the dishes out in the sun. III. Start the stopwatch. IV. As soon as the Acetone evaporates, stop the stopwatch and note the time. V. Again suck the leftover water using the Syringe OBSERVATION- Total Time Taken = 1324 seconds. VOLUME RATE OF LIQUI INITIA FINAL EVAPORAT EVAPORATI D L VOLU ED ON VOLU ME ME Water 5.0 ml 4.6 ml 0.4 ml 0.00030ml/sec 11  Aceton 5.0 ml 0.0 ml 5.0 ml 0.00378ml/sec e CONCLUSION- As we know from our previous knowledge that bond in water is much stronger than in Acetone. Hence, we can conclude that rate of Evaporation is more in the compounds that have weak bonds. 12  EXPERIMENT-2 AIM- To study the effects of surface area on the rate of evaporation of Acetone. REQUIREMENTS- Two Petri dishes (2.5cm diameter and5cm diameter), 5ml syringe, stopwatch and Acetone. PROCEDURE- I. Wash and clean the petri dishes II. Using the syringe, suck 5ml of the Acetone and then pour it in the petri dishes. III. Put the dishes out in the sun and start the stopwatch. IV. As soon as Acetone gets evaporated in any one of the petri dishes, stop the watch and note down the time. V. Again such the leftover Acetone using the syringe and measure its amount. OBSERVATIONS- LIQUI INITIAL DIAMETE TIME RATE OF D VOLUM R TAKE EVAPORATIO E N N Water 5.0ml 2.5cm 2240 0.00221ml/sec sec Acetone 5.0ml 5.0cm 1320 0.00378ml/sec. 13  sec CONCLUSION- From this, we can conclude that rate of Evaporation increases with the increase in surface area i.e. It is directly proportional to surface area. 14  EXPERIMENT-3 AIM- To study the effect of air current on the rate of evaporation using Acetone. REQUIREMENTS- Two petri dishes, 5 ml syringe, a table fan, a stopwatch and acetone. PROCEDURE- I. Clean the Petri dishes and put in the Acetone using the5ml syringe. II. Put one of the other petri dishes under the table fan while the other in a place where there is no air current and start the stopwatch. OBSERVATIONS- LIQUID INITIAL AIR TIME RATE OF VOLUME CURRENT TAKEN EVAPORATION Acetone 5ml Yes 843 0.0059ml/sec seconds Acetone 5ml No 1623 0.0030ml/sec seconds CONCLUSION- From this experiment, we can conclude that with increase in the flow of air current, rate of evaporation increases. Hence, rate of evaporation is directly proportional to the flow of air current. 15  EXPERIMENT-4 AIM- To study the effect of temperature on the rate of evaporation. REQUIREMENTS- Two beakers, 5ml syringe, a stopwatch, burner, water bath, thermometer and Acetone. PROCEDURE- I. Wash and wipe dry the beakers. II. Using the syringe, take 5ml of the Acetone and then pour in water in the two petri dishes. III. III. Heat the water bath to a constant temperature around 70˚C and note the time taken by it to evaporate completely. IV. When the Acetone evaporates completely, suck the leftover in the other petri dish in the syringe and measure its volume. OBSERVATIONS- Total Time- 660 seconds LIQUI FINAL TEMPERATU RATE OF D INITIAL VOLUM RE EVAPORATI VOLUM E ON E Aceton 5ml 0mL 70˚C 0..0075ml/sec e 16 Aceton 5ml 3.8ml Room 0.0018ml/sec e Temperature (Approx 30˚C) CONCLUSION- The observations indicate that the rate of evaporation of Acetone increases with the increases in temperature. Hence, rate of evaporation is directly proportional to temperature. 17  CONCLUSION After performing all the four experiments, we can conclude that rate of Evaporation of a liquid increases within  The increase in Volatility (Volatility of Acetone is very large as compared to that of water )  The increase in surface area of liquids.  The increase in flow of air current.  The increase in Temperature. 18  BIBLIOGRAPHY https://www.sciencedirect.com/topics/engineering/evaporation-rate https://en.wikipedia.org/wiki/Evaporation https://www.britannica.com/science/evaporation https://www.teachoo.com/ https://www.toppr.com/ 19