Test Tube, Porcelain Spot Plates, And Watch Glass

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Laboratory equipment that can be used as a container to identify a chemical substance is test tube, porcelain spot plates, and watch glass. The test tube is made of glass, transparent, colorless, can be heated in a direct flame or heated in water or in a tool such as autoclave in accordance with the temperature needed. The test tube is shaped like a pipe of which one end is open or has no lid. test tube has a diameter of approximately 2 cm with a height of 10 to 15 cm. The test tube is used for mixing or reacting chemicals, or can be used as containers agar in microbiology lab with a lid that is used is a sterile cotton.

If in hot conditions, tube clamp made of wood can be used to hold the test tube. Clamp tube shaped like a pair of scissors, but not sharp, in the middle there is a perforation circle as a place to clamp the test tube. Tube clamp has a thickness of 1 cm and colored wood is light brown. a tube rack is used To enforce or holding a test tube so it does not roll or fall. Tube rack made of wood or stainless steel, in the form of rectangular boxes that have shelf-perforation perforation as a place to enter the tube. The test tube can also be used as a container of the pipette, such as graduated pipette, Pasteur pipette, and volumetric pipette. So that the tip of the pipette that is being used is not dirty. How to use it is insert the tip of a pipette to take a liquid and then put into a test tube, these two tools can be stored in a table or can be stored in a tube rack, so that the position of pipettes and test tubes in a standing position.

When mixing two different liquids in test tubes, it's rather difficult to stir, since the diameter of a test tube is small, if inserted stir bar will increase the volume of the substance contained in a test tube and might overflow. If the test tube shaken by hand, the two fluids will be mixed but not optimal. the centrifuge machine is to stir the liquid in a test tube so it can mixed perfectly.

Centrifuge machine is a machine that in the middle of it there is a circle made by metal plate coated with rubber. This tool has a working principle based on centrifugal. The metal is rotating at high speed. Speed can be adjusted as needed. If a test tube putted on top of the substances contained in the tube will spin faster and stirred perfect, but the test tube must be held in tandem. If there are deposits of a substance in a test tube, the sediment will condense and separate from the solution.

The test tubes can also be used as a agar container in the microbiology lab. How to use it is, pipette 10 ml of agar solution, and then insert it into the test tube. Then close the tube with cotton so that there is no substance that can enter into the tube or out of the tube. After that unites the test tubes containing a agar solution, for example 10 test tubes and tie with using rubber bands or straps. So that it can stand. Then wrap in paper and put in the autoclave to sterilize.

After sterilization in autoclaves, test tubes will be hot and the agar in liquid form. After stored at room temperature until cool, put them in the refrigerator so it can be used in the long term. If the media want to be used, then grab a solid agar medium from the refrigerator and open the paper wrapping paper and place the test tubes in a rack tube. Do not open the cotton cover tube before it will be used to keep the media remain stable.

Before and after using the test tubes, it must be washed with water and then with soap, and the inside of the tube thoroughly with a brush to clean the tube. Then the last rinsed again with water. Then rinsed with distilled water three times or dried in an oven. Or it could be drained in a tube rack by position upside down, so that the water in a test tube will go down and test tube will dry quickly.

Another tool that can be used to identify a substance is porcelain spot plates. It is made of white porcelain, a box-shaped measuring 10 cm x 10 cm with a thickness of 1 cm. At the top of the porcelain spot plates, there are small hollows semicircle with a diameter of 1 cm and depth 0.5 cm. porcelain spot plates are widely used in qualitative analysis to identify the chemical substance.

How to use the porcelain spot plates that take the substance to be identified, for example, in the form of a solution, using a Pasteur pipette and drops into one of the hollow of porcelain spot plates 2 to 3 drops, then grab a reagent with a Pasteur pipette and dropped into the above sample solution was 2 to 3 drops, See the color changes or other reaction was made. Before and after using porcelain spot plates, it should be washed with water and then with soap, and the inside of the hollow tube thoroughly with a brush to clean. Then the last rinsed again with water. Then dried in an oven or wiped with a tissue.

Another tool that can be used in identifying a substance that is a watch glass. This glass existing circular hollow in the middle. Watch glass has various size diameter of 2 cm, 5 cm, 7 cm, 10 cm, 15 cm, and etc. Watch glass are made of glass and transparent or colored green. How to use the watch glass that take the substance to be identified is, for example, solids are taken with a spoon as much as 1 gram, or a solution is taken using a pipette 1 ml, place it above the watch glass, then grab a reagent with a pipette and drop it on top of the watch glass containing sample earlier. See the changes or the reaction made.

Before and after using the watch glass, it must be washed with water and then with soap, and the inside of the hollow tube thoroughly with a brush to clean. Then the last rinsed again with water. Then dried in an oven or wiped with a tissue. Watch glass also has other functions which can be used as a cover glass beaker or Erlenmeyer. Can also be used as a container for placing solids sample or chemicals.

That is part of the lab tools that can be used to identify chemical substances in a sample or qualitative analysis.

Titration Apparatus

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Titration is used to determine the levels of a substance based on the reactions. The analysis process using titration called titrimetri or volumetric method. there is a various Titration, they are acidi alkalimetry, iodometry, reduction oxidation or redox, potentiometri, pH-metri and others. Titration can be done manually by glassware or by instrument, such as potentiometer, pH meter, or autotitrator. Titration in manual method, using a glass apparatus such as burette 50 ml, beaker 100 ml, watch glass, volumetric flask 250 ml, stirring rod, Erlenmeyer flask 250 ml, graduated pipette 25 ml, funnel glass, weighing bottle, poles, ring stand, and clamps.

All glassware should be washed with water and then with soap and brushed by the brush tubes,  then rinsed again with water. Then last rinsed with aquadeast. Burette as a place for reagent or standard solutions or titrator should be rinsed 3 times with a standard solution or titrator. Then weigh the sample or titrant into the weighing bottle by using the analytical balance (see how to use analytical balance article). For example, the sample is 1.4536 grams. Then add distilled water and mix with stir bar until everything is dissolved.

Take a 250 ml volumetric flask and then enter the solution in the weighing bottle to the volumetric flask by following the article how the use volumetric flask. Enter the standard solution into the burette using a beaker 100 ml by following the article how to use Burette, then take 25 ml solution from the volumetric flask using graduated pipette, by following the article on how to use the graduated pipette.

Put 25 ml the solution in the graduated pipette to 250 ml Erlenmeyer, add 2 drops of indicator solution. Indicator solution is a solution containing a substance that changes color when the endpoint is reached, but the substance did not participate in the reaction. Indicator solution varies depending on each reagent and the reaction. As an example for acid-base reaction is used phenolpthalein indicator. The Acid-base reaction of reactions that occur in between a strong acid and a strong base. If the solution that is in the burette one of strong acids or strong bases.

Then do titration with a standard solution from the burette. Open the tap burette so the solution drips little by little. Shake Erlenmeyer unidirectional by folloeing the article how the use Erlenmeyer. If the color changes, then close the tap Burette immediately. Not to excess, even if one drops, because the results will not be accurate. Record the volume titrator in Burette that used and calculate the concentration samples or titrant by the formula:

Concentration titrant = Concentration Titrator x Volume Titrator x mol titrant
                                                      Volume titrant

Titration using potentiometer easier to do than titration with the glassware manual method. Potentiometri is a method used by a surge in potential energy in the reaction between standard (titrator) and samples (titrant). pH meter can also be used for titration, but only on the reaction acidi-alkalimetry for endpoint was calculated based on the occurrence of a surge in pH the solution. In the event of a potential energy or the pH surges this mean the endpoint was reached and the volume of the standard solution can be calculated. It does not require the indicator solution.

How to do a titration with a potentiometer or pH meter is insert standard solution in a burette by following the article how to use Burette. Then pipette 25 ml of the sample solution or titrant from the volumetric flask using a graduated pipette. Put it in a 100 ml beaker. Place this beaker on a magnetic stirrer and insert a magnetic into it. Stir at the middle speed. Rinse potentiometer electrode or pH meter electrode with distilled water 3 times. Then dip it in solution in a beaker containing that titrant. Be careful with the magnet on the electrode. Because the electrodes can damage or even break.

Record the energy potential or pH that measured. Then drops 5 drops of standard or titrator from the burette. Let stirred by a rotating magnet for 30 seconds, record again the energy potential or pH was measured. Then repeat again until the potential energy or pH surge. It means the endpoint reached. Continue the titration process by adding 1 or 2 ml standard solution from a burette. And still record the energy potential or pH were measured every 5 drops. Plot a graph of the potential energy with burette volume or pH with volume burette. Specify endpoint through this graph. Calculate the concentration samples or titrant by the formula above. If you have finished using electrodes on potentiometer or pH meter, it must rinse with distilled water and put in a buffer solution by following the article on how to use a pH meter.

Autotitrator is an instrument that can automatically perform a titration based on the potentiometri. Autotitrator is the easiest, fastest, and most modern titration. In autotitrator are a bottled as a place to store standard solution or titrator. In the bottle there is a small hose that can be connected into a beaker or cup reaction. There's another bottle as a waste storage of titration results. Autotitrator also accompanied by a small compressor to suck this waste. Electrodes connected to autotitrator and there is a plastic test tube containing buffer solution as a place to store the electrode.

Buttons on autotitrator that the on and off to switch on and off. Start and stop buttons to start and stop the titration process. The number keys to enter the data and the key to run the program or calculate titration process. Button compressor to suck waste titration results. Autotitrator Titration is based on the occurrence of the potential energy surge in reactions that occur. Autotitrator also comes with a magnetic stirrer for stirring the solution. A small printer is also connected with autotitrator to print the results of the titration.

How to use autotitrator that enter a standard solution into standard bottles. Also fill the small hose until full. There must be no air bubbles in the hose. Set parameters at titration program, the input concentration of standard solution or titrator, the weight of the sample is weighed, volume volumetric flask and volume graduated pipette used  for sample or titrant. Then take 25 ml of the sample solution with graduated pipette and put in a beaker of 100 ml.

Place this beaker on a magnetic stirrer. Take the electrode and rinse with distilled water. Enter the electrode and standard solution or titrant hose into a beaker of 100 ml. Dip up to 1 cm above the base solution. Then insert a small magnet into a it. Turn on the magnetic stirrer so that the magnet rotates. Set the speed at medium speed. Be careful with the magnet on the electrode. Because the electrodes can damage or even break. Press the start button so the titration starts.

When a surge of energy potential and the titration end point is reached, stop the titration process by pressing the stop button. Or if it is known to estimate the volume that will be used in the titration process, you can set the volume of the standard solution in the titration program. At the time this volume has been reached, then the titration process is automatically terminated. Do not let the titration end, if the endpoint has not been reached. Meanwhile, volume that was set before has been reached and the titration process is automatically terminated, the titration process must be repeated because it has not reached the endpoint. At the time of the titration process is ended, then the printer will automatically print the titrant or sample concentration along with the parameters used. No need to count again manually.

That's part of the tools used in the lab, from manual to modern titration.

Litmus Paper, Universal Indicator Test Kit, and pH Meter

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The most easily measured pH is in liquid form. The pH of a solution depends on the degree of ionisation of an acid or alkali as well as how concentrated or dilute it is. The pH level range is from 1 to 14. The pH of 1 is the most acidic, pH 7 is pH neutral, and a pH of 14 is the most alkaline. pH also affects the taste, pH of 1 to 6 have a sour taste, the higher the levels of pH, the more acidic is in it. pH 7 has a neutral taste. pH 8 to 14, has a bitter taste.

The liquids that have pH 1-2 or pH 13-14 is corrosive that can damage or blistered skin, clothing, or other organic materials. pH 1-2 is owned by the acid solution saturated or concentrated acids, while the pH is 13-14 owned if an alkaline solution saturated or base slab. And pH 7 is owned by water or distilled water. Therefore distilled water is often used as a solvent in a wide variety of needs in the lab. And also a pure liquid is distilled water does not contain minerals, salts, or other materials.

To measure pH, tools that can be used is a litmus paper, universal indicator test kit, and a pH meter. Litmus paper is the simplest pH measuring device and can only show acidic or alkaline. Litmus paper have 2 typed, there are blue and red. Litmus paper sheets shaped like a small book 2 cm x 5 cm. Litmus paper can be cut with scissors as needed.

How to use Litmus to measure acidic solution is take the blue litmus paper with your fingers or tweezers clamp. Then enter into the solution, and lift. Do not be too long dip litmus paper, only 1 or 2 seconds will suffice. Then dry with fanned the edges with your fingers or tweezers clamp. If the litmus paper turns red it means the solution is acidic. But if the pH indicator paper remains blue it means neutral or alkaline solution.

How to use litmus paper to measure the alkalinity solution is take the red litmus paper with your fingers or tweezers clamps. Then enter into the solution, and lift. Do not be too long dip litmus paper, only 1 or 2 seconds will suffice. Then dry with fanned the edges with your fingers or tweezers clamps. If the pH indicator paper turns blue it means alkaline solution. But if the litmus paper remains red then it means a neutral or acid solution.

Universal indicator test kit to measure pH more accurately than the litmus paper. This universal indicator paper shaped sheet of paper and thicker than litmus paper, 0.5 cm x 5 cm, and have 4 different colors. This color is the main component of indicator universal consisting of materials (from top to bottom) of thymol blue, methyl red, bromothymol blue and phenolphthalein. The fourth material will change color  if given acid or base on it. The universal indicator paper has a standard color as a benchmark in determining the pH measurement. The pH standard back panel of the packaging universal indicator. pH standard consists of four color combinations of pH 1 to pH 14. Any pH level has a different color combination.

The universal indicator paper can be cut with scissors as needed, but each piece must contain all the colors that can be read and compared with a standard color. How to use universal indicator paper pH is take the paper with your fingers or tweezers on the top of the white paper or part no color combinations. Then enter into the solution, and lift. Do not be too long dip universal indicator paper, only two or three seconds is enough. Then dry with fanned the edges with your fingers or tweezers clamps. If it is dry, compare with a standard color that is behind the packaging. To determine the pH, match the color combination universal indicator as the pH standard.

Another tool is very accurate in measuring the pH, that is the pH meter. pH meter uses electricity as its energy source and has a screen that can display the measured pH. Measuring pH with a pH meter could be up to 2 digits behind the comma, for example 4.68. pH meter has a measuring device which is pH electrode that is shaped like a test tube, with liquids in it. Around these electrodes there is a protective glass so the solution is more stable and faster pH measuring.

If this tool is not used, to maintain the electrodes with the situation is the electrode dipped into the liquid. The button was in the pH meter is on and off button, to turn on and turn off the pH meter. And the calibration button, used during calibration of the pH meter. PH meter calibration is made to maintain the accuracy of the measurement of pH. Calibration is performed periodically, for example, once a month. At the time of the calibration standard pH buffer solution used is pH 4, 7, and 10. The pH measurement first do with a pH of 7 because it is pH neutral, then with pH 4 and pH 10 or vice versa pH 10 and pH 4.

How to use pH meter is press the button on to turn on the pH meter. Then grab the electrode from the handle with one hand. The tip electrode is rinsed with distilled water and wipe with a soft tissue. Do not use tissue roughened, electrode surface can be scratched and reduce the accuracy of pH readings. Then reattach to the handle, dip the electrode in the solution to be measured. Dip up to 1 cm from the bottom of the solution. Wait until the pH scale on the screen does not move anymore or stable. Write down the measured pH. Then grab the electrode and rinse with distilled water and then wipe using a soft tissue. Return the electrode by its handle and insert to the electrode fluid. Turn off the pH meter by pressing the off button.

That is part of the lab tools that can be used to measure pH from the most inaccurate until the tool most accurate pH measurement.

Quantitative Filter Paper, Buchner Funnels, And Separatory Funnel

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The tools in the lab that used for separating substances, both solids from the liquid or fluid from the fluid, among which is the quantitative filter paper, buchner funnel, and separatory funnel. The quantitative filter paper, is sized to vary according to the size of particles precipitate is filtered. The filter paper in the form of a white paper that is circular with a diameter diverse. Filter paper no. 40, 41, and 42 is a filter paper that is most widely used in laboratory analysis.

To use a quantitative paper filter for filtering with an additional tool is using a glass funnel manually or using a buchner funnel. If filtering with quantitative filter paper and funnel glass, the precipitate filtered using quantitative  filter paper according to the size of the particles of the substance to be filtered. How to attach the quantitative filter paper in the funnel so that the screening process faster is by folding the filter paper into ½ part, press one side of the fold, then fold the filter paper into ¼ sections so that the filter paper is now smaller in size than the glass funnel.

Insert quantitative filter paper into a funnel glass and quantitative filter paper paste on the wall of the funnel with a little aquadest. Hold the mouthpiece with one hand. Cover the bottom of the funnel pipe with the index finger. And the position of the hand with the fingers grasping the funnel. Add distilled water into the filter paper and funnel to exceed the height of distilled water filter paper. Then release the index finger that closes the pipe so that the distilled water will come out of the pipe and the bottom of the funnel, so that no air bubbles between the bottom of the filter paper and pipe, mouthpiece must contain distilled water. In this way the screening process will be faster.

If distilled water in the filter paper has run out, pour a solution containing sediment that will be filtered into the filter paper by means of stick rod on the wall of filter paper in an upright position, then pour the solution on a stir bar until 1 cm below the height of filter paper. This is done so that there is no solution that spills out during filtration.

The buchner funnels filtering is easier and faster than with manual funnel glass. Buchner funnels is a set of tools consists of several tools which is erlenmeyer-legged on top, ring a filter paper, funnel and compressors. Before use, erlenmeyer, rings, and funnel should be washed with water and then with soap and brushed with a brush tube. Then dried in an oven or drained. Cut a quantitative filter paper into small spheres in the size of the ring and place it over the ring. Place the ring along with the filter paper over erlenmeyer then place the funnel on it. Turn the funnel so that all three devices are united and there are no leaks.

Paste stirs bar in the middle of the funnel and then pour the solution containing the precipitate to be filtered into the funnel through the stir bar. Connect the compressor hose to the pipe erlenmeyer. Turn on the compressor to suck air. And the solution is in the funnel sucked down into the erlenmeyer and sediment will be left on the filter paper.

The next tool is used for separating a substance in a liquid with another liquid that is separatory funnel. This funnel made of glass, shaped like a pear that is getting down increasingly cone, at the top there are a lid. The bottom of the funnel there is a tap that can be opened or closed to remove the solution. Then after the tap there is a small pipe as where the flow of the solution in a separating funnel out.

The working principle of a separatory funnel is based on the differences of the solubility properties of a substance dissolved in the solution. How to use a separatory funnel is enter 100 ml of a solution containing the substance to be extracted into a a separatory funnel and then enter 50 ml of solvent. There will be two phases in this solution. The solvent is at the bottom. Whisk strongly in one direction, upwards and then downwards, with the position of the top of the funnel is below. Whisk for 30 minutes.

At the moment shaken, open sometimes the tap to remove the air. Be careful, don't face it, because the vapor may be harmful if inhaled by the nose. Then let the separatory funnel for 30 minutes, so that the two-phase solution coating can be seen clearly. Open the tap funnel so that the solvent will flow down out of the separating funnel. Absorb these solvents. Be careful not to get the solution in above phases come pouring down out with solvent.

Then reinsert the 50 ml of solvent. Whisk strongly in one direction, upwards and then downwards, for 30 minutes. Then let stand for 30 minutes, open the faucet funnel so that the solvent will flow down out of the separatory funnel. Absorb these solvents with the same container with the first shaking. Repeat this process until 5 times and so that substances extracted completely dissolved in the solvent.

Another tool that can be used to separate a substance that centrifuge machine. but the only substance in the form of sediment in solution only that can be separated with this tool. This machine works by centrifugal force. Centrifuge machine is a machine that in the middle of it there is a circle made by metal plate coated with rubber. The metal is rotating at high speed. Speed can be adjusted as needed. If a test tube putted on top of the substances contained in the tube will spin faster and stirred perfect, but the test tube must be held in tandem. If there are deposits of a substance in a test tube, the sediment will condense and separate from the solution.

That is, a few of the tools that are used to separate substances that are used in the lab.

Distillation Apparatus

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Distillation is the process of purification of a substance that can be derived from solids or liquids from differences of boiling point. The principle works are a mixture of substances that is boiled to evaporate, and the steam then cooled so that back into a liquid form. Substances which have a lower boiling point will evaporate first and separated from the mixture.

Distillation is a physical process and does not happen to a chemical reaction during the process so that there is no change whatever happens. There is only a process of separation or purification of a substance from a complex material by using certain solvents. In the distillation process contained lab apparatus is bunsen or heater, destilling flask, distillation adapter, thermometer, condenser, receiver adapter, erlenmeyer flask or receiving flask, water hose, clamp, ring stand, tripod, heatproof mat.

The distillation process which is simple distillation, fractional distillation, steam distillation, vacuum distillation and so on in accordance with their respective functions. Simple distillation is used to separate one substance miscible with other substances. For example, water containing minerals or metals, salts, and others, to split water into pure water H2O then do a simple distillation process.

How to assemble the distillation apparatus is destilling flask placed in a round heater or over a bunsen. Place tripod above the bunsen, then heatproof mat on top, and destilling flask over heatproof mat. Do not light the bunsen. Then enter 50 ml the sample water into destilling flask. Enter boiling stones into a destilling flask. Boiling stones function so that bubbles out to be smaller and to avoid splashing strong. Boiling stones are made of porcelain, irregular shape and magnitude of approximately 1 cm. Attach the clamps to the neck of the destilling flask so that the flask can stand firmly. Attach the other end of the clamp to the ring stand. Then attach the distillation adapter rounded upwards. This tool has two apertures, as a place to put a thermometer and as a channel for water vapor to the condenser.

Attach a thermometer on top of the distillation adapter. Then place the condenser at the other end of the distillation adapter. Attach the clamp to hold the condenser. Attach the other end of the clamp to the ring stand. Angle the condenser so the other end is lower. The condenser has a 4 hole that is 2 holes for tap water channels in and out. And two other holes to be connected to the distillation adapter and into the receiver adapter as a channel of water vapor from the distillation adapter. Then put the water hose to the water faucet at the sink. End of the hose is coupled to the lower condenser channel position. Take the other hose and then attach it to the condenser channel a higher position. End of the hose is placed in the sink. The tip of the condenser is connected to the receiver adapter. Under the receiver adapter is placed the erlenmeyer flask or receiving flask.

Open the tap water in the sink so that the water flows into the condenser. Water flows from the bottom to the top of the condenser. Do not reverse installing the hose, because it can result in water flow in the condenser from the top to the bottom. If this happens then there will be an air cavity and not all the cool room will be filled with water. And cooling processes to be not optimal.

Turn on the bunsen and open the oxygen ring to produce two layers of flames, blue and green. The water in the destilling flask will boil and only pure water or H2O that will evaporate. Minerals, metals, salts, and so mixed in water will be left in the destilling flask. The thermometer at the top of the distillation adapter will show the temperature. Check the temperature, it must be not more than the boiling point of water which is 100°C. If the thermometer temperature over 100°C, lower temperatures by reducing the bunsen flame. Water vapor from the destilling flask will enter into condenser. The tap water that flows into the condenser will cools the steam coming out of the destilling flask that turned into a moisture.

Because condenser position is sloping downwards, it will facilitate the moisture formed to flow into the receiver adapter. Pure water (H2O) that goes into the receiver adapter will flow into the erlenmeyer flask or receiving flask under the form of droplets. Droplets of water collected in the erlenmeyer. The pure water as a result of distillation process called distilled water.

Glass apparatus such as destilling flask, distillation adapter, condenser, receiver adapter, erlenmeyer flask or receiving flask, before and after use should be washed with water and then with soap and brushed with a brush tube. Then with water and dried. Destilling flask, erlenmeyer flasks or receiving flask can be dried with a tissue or with drained. The distillation adapter, condenser, receiver adapter, can be dried in the oven.

Applications of distillation process can be divided into two types of distillation, they are in laboratories and in industry. The main difference distillation in laboratories and in industry is the implemented system. In the laboratory distillation process is performed only once, while in the industrial distillation is done on continual process. In the sense of the distillation in the laboratory, the composition of the mixture is separated into component fractions are sorted by volatility, in which the most volatile substances to be separated first. The least volatile substance will be left on the bottom. This process can be repeated when the mixture is added and begin the process of distillation back. In industry, the material to be distilled remain in a fixed composition. Desired substances are separated from the system carefully, and when the starting material runs out it can be added again without stopping the process of distillation.

Lots of products made by the process of distillation. for example, alcohol formed from the fermentation process also purified by distillation. Natural oils are made with distillation processes, for example, ginger oil, olive oil, clove oil, eucalyptus oil and so on. Even oils from soil, distillation is a key element in the separation of petroleum fractions based on boiling point.