Follow us at: https://plus.google.com/+tutorvista/Check us out at http://chemistry.tutorvista.com/physical-chemistry/reaction-rates.htmlReaction RatesAs you . Now we change the concentration and measure the initial rate (state 2). Lets look at a system involving three reactants, \[A + B + C \rightarrowProducts \\ R=k[A]^m[B]^n[C]^p\]. The mark X is viewed vertically from the top through the solution, as shown in Figure. In this graph, the blue line 2M concentration was steeper than the orange line 1M concentration over the time frame after 7 minutes, which showed a faster rate of reaction. For example: 40 mL of HCl would be 40.5 or 39.5 mL. This corresponds with the hypothesis and indicates that enzyme activity is more efficient at pH levels closer to the optimum pH, which is at 7 or neutral. Effected on the reliability of the experiment, especially the accuracy of reaction rate. () i ii () ii iii () i iii () i, ii iii, iron nails were dipped in solution kept in the test tube after half an hour it was observed that the colour of the solution had changed the solution p Start the timer. The error while doing experiment can also be reduced by minimised the mistakes while performing experiment (details in Limitation), especially random errors. Students should be able to recall how changing these factors affects the rate of chemical reactions. Effects Of Faith In Night By Elie Wiesel 1146 Words | 5 Pages. Determine the value of m (at constant[Cl2]): Using the third trial and the first trial: After canceling equivalent terms in the numerator and denominator, we are left with: We can use the log of any baseto determine the value of the exponent m,(we used base 10 in the worked out example above, and will use natural logs here). Aluminium sulphate , What is froth-floatation process? 2) Increasing the concentration of the reactants or the pressure of gaseous reactants. So you design a series of experiments where two of the concentrations are constant and vary the third to see how it affects the rate. reaction rate. 5. (*)HCO3 + OH = CO+Hp0 | () NH + H = NII(1) CaO + 2H = Ca +H20 () NaH + HI) = NaOH + H,| H,SO = | () 98g() 9.8g() (0.982| () (0,000| ? C Because the reaction rate is independent of the N 2 O concentration, doubling the concentration will have no effect on the reaction rate. Usually reactions speed up with increasing temperature. (This value can be taken as a measure of the rate of reaction). 2. Did not use finger to clean up broken glass. Explain the effects on rates of reaction of changes in temperature, concentration and pressure in terms of the frequency and energy of collision between particles. 4. This is due to an increase in the number of particles that have the minimum energy required. Use of: graduated glassware (volume) such as measuring cylinders of varying sizes; Unit 2: Further Chemical Reactions, Rates and Equilibrium, Calculations and Organic Chemistry, 2.3.1 demonstrate knowledge and understanding that the rate of a reaction may be determined by measuring the loss of a reactant or gain of a product over time and use the equation: rate = 1 / time, 2.3.2 suggest appropriate practical methods to measure the rate of a reaction and collect reliable data (methods limited to measuring a change in mass, gas volume or formation of a precipitate against time) for the reaction of: metals with dilute acid;, 2.3.3 interpret experimental data quantitatively, for example drawing and interpreting appropriate graphs to determine the rate of reaction; and, Unit C2: Further Chemical Reactions, Rates and Equilibrium, Calculations and Organic Chemistry, 2.3.2 suggest appropriate practical methods to measure the rate of a reaction and collect reliable data (methods limited to measuring a change in mass, gas volume or formation of a precipitate against time) for the reaction of: metals with dilute acid, Mandatory experiment 6.2 - Studying the effects on the reaction rate of (i) concentration and (ii) temperature, using sodium thiosulfate solution and hydrochloric acid, Demonstrating the importance of surface area to rates of reaction, Gold coins on a microscale | 1416 years, Practical potions microscale | 1114 years, Antibacterial properties of the halogens | 1418 years, Dilute hydrochloric acid is low hazard at the concentration used (see CLEAPSS Hazcard. Swept up the fragments glass with dustpan or brush. What is the collision theory in chemistry? How is the rate constant related to the concentration? The graph illustrates approximately linear relationships (first-order relationship) for the three concentration (independent variable) through the corresponding of CO2 gas produced and the concentrations. The Rate Law is a power function that describes the effect of theconcentrationof the reactants on the rate of reaction for a reaction occurring at constant temperature. Set up apparatus a shown in the diagram or according to your teachers instructions. Changing the concentration or temperature of the solutions changes the time required for the blue colour to develop. m=3(Third Order Reaction): This is a cubed relationship and if you double the concentration it goes eight times faster. 4.7.4.1 Factors that affect reaction rates. Temperature. There will be more collisions and so the reaction rate is increased. Explain the effect of concentration on the rate of reaction? Weigh out 1 g of marble chips and add them to the conical flask. Whether you need help solving quadratic equations, inspiration for the upcoming science fair or the latest update on a major storm, Sciencing is here to help. For gases, increasing pressure has the same effect as increasing concentration. Describe the effect of changes in temperature, concentration, pressure, and surface area on rate of reaction. Does concentration affect reaction order? Best Match Question: In 2-3 sentences; explain the general trends of how chemical reaction rates are affected by concentration: Also, provide one real life example of the influence of concentration 0n the reaction rate of a chemical process_ For the toolbar, press ALT+F10 (PC) or ALT+FN+FIO (Mac) Difference in surface area will affect the reaction rate of concentration because a high surface area produces a faster reaction rate and low surface area produces a slower reaction rate, which affect the accuracy of the results and decreased the validity. What 4 factors affect the rate of a reaction? The rate of an enzyme-catalyzed reaction increases with an increase in the concentration of an enzyme. The conical flask is placed on top of a piece of white paper with a mark X at the centre. This experiment uses simple chemicals and equipment found in your learning space. Often there is more than enough of one reactant, and the rate of the reaction depends on the other reactants present. (a) For example, two sets of experiments are carried out using the reacting conditions below: Set I: 1 g of zinc powder and 20 cm 3 of 0.4 mol dm -3 hydrochloric acid at room temperature. Rates of Reaction. 1) Using a Sharpie, draw a black X on the bottom (outside) of each beaker. Thus, it implies that the concentration of sodium thiosulphate solution is directly proportional to 1/time. Author: Fred Senese senese@antoine.frostburg.edu, Copyright © 1997-2010 by Fred SeneseComments & questions to fsenese@frostburg.eduLast Revised 02/23/18.URL: http://antoine.frostburg.edu/chem/senese/101/kinetics/faq/everyday-kinetics.shtml, http://antoine.frostburg.edu/chem/senese/101/kinetics/faq/everyday-kinetics.shtml. The term is also used more generally to characterize any type of exponential (or, rarely, non-exponential) decay. Add the acid to the flask and immediately start the clock. What are everyday examples of concentration effects on reaction rate? Use this practical to investigate how solutions of the halogens inhibit the growth of bacteria and which is most effective. If a chemist wants to increase the rate of a reaction, an increase in the concentration of one or more of the reactants will do the trick . In a reaction where both reactants are in low concentrations the particles are spread out and will collide with each other less often resulting in fewer successful collisions. First take the log of both sides, Using the relationship lnab= lna+ lnb gives, then using the relationship \(log[A]^b=blog[A]\) and rearranging gives, which has the form of a straight line with slope=m, To get k you take the antilog of b Here are 10 examples of rates in everyday life 1. Rate equations take the form: k is the rate constant. How does the temperature affect the rate of a chemical reaction? Measuring cylinder: try to put at the same height or eyes level for every trial so that the results are read at the same angle, which decrease the uncertainties of HCl used. Would love your thoughts, please comment. In general, the transition state of a reaction is always at a higher energy level than the reactants or products, such that E A \text E_{\text A} E A start text, E, end text, start subscript, start text, A, end text, end subscript always has a positive value - independent of whether the reaction is endergonic or exergonic overall. Table illustrates some examples. The more concentrated the faster the rate (note in some cases the rate may be unaffected by the concentration of a particular reactant provided it is present at a minimum concentration). Determine the numerical value of the rate constant k with appropriate units. Similarly, from 6 minutes to 7 minutes, the linear was getting wiser as the reaction rate of 2M acid is the highest (30.29 mL/min). \(\color{red}{\textbf{Increasing the surface area of the reactants increases the rate of the reaction. Thus, Eliminates the amount of random error by repeating the measurements would improve the accuracy for the experiment and the final outcomes. Background information:Factors that change the rates of reactions are:Temperature - an increase in temperature will make the reaction occur faster. This support the hypothesis as well as the research question that if the surface area or temperature are kept constantly, increasing acid concentration will increase the reaction rate (Nuffield Foundation,2013). Some factors that influence the speed of a chemical reaction are: (1) surface area of starting reactants; (2) concentration of reactants; (3) temperatures. For example, if doubling the concentration of a reactant doubles the rate of reaction, the reaction is a first-order reaction for that reactant. This lesson will start by solving the single reactant rate law. The result, in the form of graphs on the computer, can be analysed using data logging software. This excites the molecules and makes them move faster and faster, eventually. Low body temperatures slow down metabolism. (a) Graph II is a straight line. Substances are either chemical elements or compounds. \[0.45^m=\frac{56.3}{32} \\ In this experiment, two colourless solutions are mixed to make a solution which becomes dark blue. When you double the concentration the rate goes up four times. Ensure good ventilation. A pH level at 4-5 is very acidic and contains more hydrogen ions . As the enzyme molecules become saturated with substrate, this increase in reaction rate levels off. RP19 Investigation of how changes in concentration affect the rates of reactions by a method involving measuring the volume of a gas produced and a method involving a change in colour or turbidity. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products. GRAPH: Illustrate the volume of CO2 gas produced of CaCO3 marble chips in different concentrations of HCl acid as time progresses with linear trendline. In this example, the concentration units are mol 3 /L 3. If weassume the orders of reaction for each reactant are independent of each other (m does not change n), we can run a series ofexperiments where we vary one reactant concentrationat a time to determine its order of reaction, whilekeeping all others constant. The reason for this trend also has to do with collisions. So, the proportion of collision depends upon the number of particles that will participate in the collision. According to the collision theory, the rate of reaction increases with the increase in the concentration of the reactants. It means the concentration of the reactant is consumed in a unit of time. Information about your use of this website will be shared with Google and other third parties. This occurs because a higher concentration of a reactant will lead to more collisions of that reactant in a specific time period. Determine the value of n (at constant [NO]). Divide the units for the reaction rate by the units for all species in the rate law to obtain the units for the rate constant. The conical flask is then placed back on the white paper. This material has bothoriginal contributions, and contentbuilt upon prior contributions of the LibreTexts Community and other resources,including but not limited to: This page titled 14.4: Effect of Concentration on Reaction Rate is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Robert Belford. The catalytic decomposition of hydrogen peroxide Solid manganese (IV) oxide is often used as a catalyst in this reaction. For example, when small pieces of the metals iron and sodium are exposed to air, the sodium reacts completely with air overnight, whereas the iron is barely affected. The units for k should be mol 2 L 2 /s so that the rate is in terms of mol/L/s. The order of reaction is found experimentally by changing the concentration of reactants and observing the change in the rate of reaction. The enzyme rate of the reaction showed an increase during pH levels at 8-9. If the concentration or pressure is increased:. The sulphuric acid is then poured quickly and carefully into the conical flask and a stopwatch is started immediately. Paul Andersen 2013, The Rate Of Reactions, Bozeman Science, viewed 19 May 2020. Measure the temperature of 50 mL of 2M HCl and add to the conical flask and quickly put the cork on the flask. 5 What happens when the concentration of an enzyme increases? Lumen 2019, Factors that affect reaction rate, viewed 19 May 2020. A decrease in particle size causes an increase in the solid's total surface area. Catalysis is the backbone of many industrial processes, which use chemical reactions to turn raw materials into useful products. Zinc and hydrochloric acid In the lab, zinc granules react fairly slowly with dilute hydrochloric acid, but much faster if the acid is concentrated. Add all exponents to obtain the overall reaction order. Effect of concentration on the rate of reaction, Effect of concentration on the rate of reaction experiment. m = 0 (Zero Order Reaction): Here the rate is not affected by the concentration and if you were to double the concentration the rate would not change. Reaction rate can be written for the disappearance of a reactant or the appearance of a product. Catalysts are integral in making plastics and many other manufactured items. The total volume of each solution should be the same in each beaker. Bread dough rises more quickly in a warm place than in a cool one. ( Class 10-based answer please!!! Random error: Meniscus levels, as the HCl was measured by different individuals in each trial allowing different amount of HCl present in the reaction. Higher concentrations of acid in rain erode marble faster than lower concentrations. How to Market Your Business with Webinars. For the reaction of calcium carbonate and hydrochloric acid to produce carbon dioxide and calcium chloride, the carbon dioxide can be collected as well. Does rate constant depend on concentration? According to Collision theory, the greater the frequency of successful collisions, the greater the rate of reactions (Nuffield foundation,2013). 10.1 Rates of Reactions. The rate law for this reaction will have the form: 1. To determine the value of k once the rate law expression has been solved, simply plug in values from any experiment, we will use the first experimental trial because the math is easiest, and solve for k: Robert E. Belford (University of Arkansas Little Rock; Department of Chemistry). As the CO2 released, the rate of reaction will decrease so that may weakness the validity of experiment and reliability of the result at the end. Conversion between two measurement systems Many problems require changing from one type of measurement unit to another. Anything in a square bracket ( [ ]) just means we are referring to the . Good Science 2020, Rate of a Chemical Reaction, viewed 19 May 2020. Overall, concentration is only one factor influencing the rate of reaction, and the relationship is usually not simple or linear. Online he has written extensively on science-related topics in math, physics, chemistry and biology and has been published on sites such as Digital Landing and Reference.com He holds a Bachelor of Science degree from McGill University. Typically the acid reacts with magnesium atoms from the metal, and as the metal is eaten away, the reaction proceeds. Katherine (sevenmagic@usa.net) Here are just a few everyday demonstrations that temperature changes the rate of chemical reaction:Cookies bake faster at higher temperatures.Bread dough rises more quickly in a warm place than in a cool one.Low body temperatures slow down . -Reacting molecules must collide, have a minimum amount of energy, and have the proper orientation to form products. Depending on the reaction, it is usually easiest to measure one of the most accessible and easily observed substances. When you double the concentration the rate doubles. Low body temperatures slow down metabolism. An easier method might be to weigh the reaction container to determine how much carbon dioxide has been given off. Depending on the specific situation, changing the concentration of one reactant may have no effect. In this experiment,the highest concentration of HCl (2M) had the highest average rate of reaction (30.624 mL/min) after 7 minutes. We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. Cookies bake faster at higher temperatures. The trendline of 0.5M illustrates the lowest rate of reaction as it was dropped to 7.27mL/min and the smallest amount of gas was produced over this time (42 mL). ), Which of theseis not abase quantity in mechanics? Difference in surface area: To control the surface area, CaCO. The concentration of A decreases with time, while the concentration of B increases with time. Table 13.3.3 Rate Data for a Hypothetical Reaction of the Form A + B Products, \[ \frac{rate_{2}}{rate_{1}}= \frac{k[A_2]^m[B_2]^n[C_2]^p}{k[A_1]^m[B_1]^n[C_1]^p} =\frac{{\color{Red} \cancel{k}}[A_2]^m[0.1]^n[0.1]^p}{{\color{Red} \cancel{k}}[A_1]^m[0.1]^n[0.1]^p} \nonumber\], \[\frac{R_2}{R_1}=\left ( \frac{A_2}{A_1} \right )^m {\color{Blue} \cancel{\left ( \frac{0.1}{0.1} \right )^n}} {\color{Red} \cancel{\left ( \frac{0.1}{0.1} \right )^p}} \nonumber\], \[\frac{R_2}{R_1}= \left ( \frac{A_2}{A_1} \right )^m \\ \frac{0.019{\color{Red} \cancel{M}}}{0.00475{\color{Red} \cancel{M}}} =\left ( \frac{.20 {\color{Red} \cancel{M/s}}}{.10{\color{Red} \cancel{M/s}}} \right )^m \\ \;\\4=2^m \\ \;\\m=2 \], Step 2: Determine nby running set of experiments at constant[A] and [C] constant Chemical reaction: Hydrochloric acid + Calcium Carbonate -> Calcium Chloride + Carbon Dioxide + Water 2HCl (aq) + CaCO 3 (s) -> CaCl 2 (aq) + CO 2 (g) + H 2 O (l) Methodology: However, it is very important to keep in mind that the addition of a catalyst has no effect whatsoever on the final equilibrium position of the reaction. Rate= change in concentration/change in time. The Future Of Meat: Laboratory Grown Meat. Write the rate law for the reaction. Some reactions take hundreds, maybe even thousands, of years while others can happen in less than one second. Physical state of the reactants and surface area. Using the collision theory, explain how increasing the concentration of sodium thiosulfate can increase the rate of reaction. The smaller the piece of wood, the faster it burns. For example, the oxidative rusting of iron under Earth's atmosphere is a slow reaction that can take many . It can be explained as follows. (a) In this experiment, conical flasks of the. Remember for gasses, increasing the pressure simply increases the concentration so thats the same thing. Experiment- Activity to measure the effect concentration has on the . However, the rest of the data was normal as it was expected, which support the hypothesis that as the control variables are kept constant, the higher the concentration, the faster the rate of reaction. (i) (ii) (iii) ? Similarly, when calcium carbonate reacts with hydrochloric acid, increasing the concentration of the acid speeds up the rate of reaction as long as enough calcium carbonate is present. The units for the rate of a reaction are mol/L/s. If such medicine will release heat during reaction in our body, it is important to make the reaction is slower, therefore ensuring the patient will not experience high fewer during medication. This practical is part of ourChemistry for Non-Specialistscollection. Enter a Melbet promo code and get a generous bonus, An Insight into Coupons and a Secret Bonus, Organic Hacks to Tweak Audio Recording for Videos Production, Bring Back Life to Your Graphic Images- Used Best Graphic Design Software, New Google Update and Future of Interstitial Ads. Will students keep track? (2006). An increase in concentration means an increase in the number of particles in the reaction. This survey should give you enough knowledge to appreciate the impact of chemistry in everyday life and, if necessary, prepare you for additional instruction in . Conclusion: When the concentration of a reactant increases, the rate of reaction also increases. Bert Markgraf is a freelance writer with a strong science and engineering background. You simply take some of it and dilute in half, and now the original solution is twice that of the diluted. , resent in the test tube was that ofi. body temperature so that their biochemical reactions run at the correct rate. mlog0.45=log\frac{56.3}{32} \\ DATA 1: Noticable change in this data was the first 1.5 minutes, the 2M acid produced less amount of CO2 gas than 1M acid, which also meant 2M acid had the lower rate of reaction over this time than the 1M acid. Note: all calculations were rounded to 2 decimal places. If you continue to use this site we will assume that you are happy with it. Identify the exponent of each species in the rate law to determine the reaction order with respect to that species. Compare the changes in initial concentrations with the corresponding changes in rates of reaction to determine the reaction order for each species. Problem statement: How does the concentration of a reactant affect the rate of reaction? This is especially true when concentrations are low and few molecules or ions are reacting. The rate is proportional to the square of the concentration of a reactant. Photosynthesis Frank Krahmer / Getty Images Plants apply a chemical reaction called photosynthesis to convert carbon dioxide and water into food (glucose) and oxygen. B.Length In the above equation we have on dependent variable (the rate), which has a value that depends on three independent variables, the concentrations of chemical species "A" and "B", and "C". The volume of CO2 gas (mL) from 0 to 250 mL was plotted on the Y-axis; whereas, the X-axis shows the time (from 1 to 7 minutes). Water spilled onto the floor could lead to slippering hazard. Increasing the concentration of one or more reactants will often increase the rate of reaction. The rate of change can be measured using the slope of the graph or the time taken for a change to occur. Sponsored by Grammarly m=\frac{log\frac{56.3}{32}}{log0.45} =\frac{0.24536}{-0.34679}= -0.7075 \nonumber\], Because the rate law is a power function we need to use logarithms to determine the order of reaction. Aim: To investigate the effect of concentration on the rate of reaction. However, the trendline was matched as it was expected, the 2M acid (32.67mL/min) had a steeper gradient than the 1M acid (26mL/min) so that the rate of reaction was higher for the 2M HCl by 6.67mL/min. ), Systematic error: Difference in surface area of Calcium Carbonate (control variable). A banana ripens in a few days, silver tarnishes in a few months, while the aging process of humans takes many years. If the amount of acid is higher in the acid rain, then it will erode marble more faster when compared to the lower concentrations. The. The equilibrium constant for the reaction is given by If the concentration of any one reactant say A is increased then by Le-Chatelier's Principle the forward reaction should be favoured so that the increase in the concentration of A is nullified. So the rate law is a power function that describes how R(the dependent variable) depends on the concentration of A (the independent variable), If there are two reactants, say A and B, then the relationship is extended to two independent variables, each with their own order of reaction, \[A + B \ \rightarrowProducts \\ R=k[A]^m[B]^n\], Each additional reaction contributes anadditional independent variable to this power function, each with its own order of reaction, and so three reactants would have the following relationship, \[A + B + C \ \rightarrowProducts \\ R=k[A]^m[B]^n[C]^p\]. A light sensor clamped against a plastic cuvette filled with the reactants substitutes for a colorimeter. There are five general properties that can affect the rate of a reaction: The concentration of the reactants. The rate of reaction in general varies directly with changes in the concentration of the reactants. The units for k are whatever is needed so that substituting into the rate law expression affords the appropriate units for the rate. Typically the acid reacts with magnesium atoms from the metal, and as the metal is eaten away, the reaction proceeds. C6.2.1 describe the effect on rate of reaction of changes in temperature, concentration, pressure, and surface area, C6.2.2 explain the effects on rates of reaction of changes in temperature, concentration and pressure in terms of frequency and energy of collision between particles, C5 Investigation the effect of surface area, concentration and temperature on the rate of a chemical reaction, C5 Monitoring and controlling chemical reactions, C5.1c describe the effect of changes in temperature, concentration, pressure, and surface area on rate of reaction, C5.1d explain the effects on rates of reaction of changes in temperature, concentration and pressure in terms of frequency and energy of collision between particles, C5.2c describe the effect of changes in temperature, concentration, pressure, and surface area on rate of reaction, C5.2d explain the effects on rates of reaction of changes in temperature, concentration and pressure in terms of frequency and energy of collision between particles, by increasing the concentration of a reactant, Unit 1: CHEMICAL SUBSTANCES, REACTIONS and ESSENTIAL RESOURCES, (b) the effect of changes in temperature, concentration (pressure) and surface area on rate of reaction. If we have bad data, like the data you use in lab, we will need to use the graphing technique. One way of increasing the rate of reaction is by increasing the concentration of Sodium Thiosulphate. Caused a difference in the number of products that were formed. Noticable change in this data was the first 1.5 minutes, the 2M acid produced less amount of CO. Zombies, Science fiction or future reality? As it reacts with the hydrochloric acid, it forms soluble calcium chloride and carbon dioxide is given off. The Holocaust affects Jews in a way that seems unimaginable, and most of these effects seem to have been universal experiences; however, in the matter of faith, Jews in the concentration camp described in Elie Wiesel's Night are affected differently and at different rates. We will also introduce two different techniques for solving these. [CDATA[ The reaction rate decreases with a decrease in temperature. Physical state of reactants. This can be done if we know the unit rate (ratio) of inches to ft. When collisions occur, they do not always result in a reaction (atoms misaligned or insufficient energy, etc.). factors affecting rate of a chemical reaction, Factors That Affect the Chemical Reaction Rate, factors that affect the rate of a chemical reaction, Factors that Affect the Rate of Reactions, how does concentration affect the rate of reaction experiment. Since the rate of reaction can be affected by a range of variables such as temperature or reactant concentration, the rate constant will also vary. Concentration of a reactant in solution. Reactants are converted into products. The rate of a reaction is the speed at which a chemical reaction happens. Repeat this using different concentrations of sodium thiosulfate solution. Copper sulphateiii. The rate of a chemical reaction can be changed by altering the concentration of a reactant in solution, or the pressure of a gaseous reactant. You can specify conditions of storing and accessing cookies in your browser. The gradients of the curves are compared to deduce the difference in rates. Thus n must be 1, and the form of the rate law is: 3. We divide state one by state 2 as we have done in the other two-state problems like the ideal gas and Henry's Law calculations. Increasing the concentration of reactants generally increases the rate of reaction because more of the reacting molecules or ions are present to form the reaction products. A reaction slows down as it proceeds. A decrease in particle size causes an increase in the solid's total surface area. Are temperature and rate of reaction directly proportional? Sometimes a reaction depends on catalysts to proceed. 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