Another way to think of enthalpy is as chemical potential energy. Microsoft powerpoint chapter 15 chemical equilibrium. Initially 4 mol of so 2 g and an unknown mass, x, of o 2 g are sealed in a 2dm 3 flask and allowed to reach equilibrium at a certain temperature. The equilibrium equation for the formation of ammonia is. Usually, this state results when the forward reaction proceeds at the same rate as the reverse reaction. Summary notes chemical equilibrium is a state in a reversible reaction when the rate of the forward reaction equals the rate of the reverse reaction. In other words, it can be used to predict the direction of a chemical reaction in response to a change in conditions of temperature, concentration, volume. Printable chemistry worksheets free pdf worksheets to download or print. Le chateliers principle predicts that the equilibrium will shift to increase the concentration of products. Le chateliers principle chemical equilibrium siyavula. A shorthand way to sum up what occurs in a chemical reaction. So some sulfur dioxide or oxygen is used to produce sulfur trioxide. Reduction and oxidation are complementary processes that involve the gain or loss of electrons.
This is very important, particularly in industrial applications, where yields must be accurately predicted and maximised. Do not circle your answers directly on the examination. In a chemical reaction, chemical equilibrium is the state in which both reactants and products are present in concentrations which have no further tendency to change with time, so that there is no observable change in the properties of the system. Both matter and heat thermal energy can enter and leave the system. Exam questions 150 1 all of the following reactions are at equilibrium. Printable chemistry worksheets chemical names and formulas. Balancing chemical equations practice problems equation balancing will make sense. Looking it up in the glossary of the textbook defines it as. Open and closed systems a reversible reaction dynamic equilibrium. When the reactants and products in a chemical equation are gases, we can formulate the equilibrium expression in terms of partial pressures usually in. Also, since the rates are equal and there is no net change in the concentrations of the reactants and the products the state is referred to as a dynamic equilibrium and the rate constant is known as equilibrium constant. Chemical equilibrium when a chemical reaction reaches a state where the concentrations of reactants and products remain constant, a chemical equilibrium has been established.
Before starting this chapter it is essential that the learners have a thorough understanding of rates of reactions and chemical kinetics as covered in chapter 7. Chemistry 12 unit 2 chemical equilibrium tutorial 6 calculations involving the equilibrium constant page 3. Com print and send pdf files as emails with any application, adsponsored and free of charge. Chemistry 12 tutorial 2 enthalpy and entropy tutorial 2 page 2 enthalpy you have probably met with the concept of enthalpy in unit 1 and in chemistry 11. Introduction to chemical engineering processesprint version. Chemistry 12 unit 2 chemical equilibrium chemistry 12. That is, when a new equilibrium is reached there will be more product than before. Chemical equilibrium 7 grade 12 c hemistry topic 4.
Here we have given ncert class 10 science notes chapter 1 chemical reactions and equations. Cbse class 10 science notes chapter 1 chemical reactions and equations pdf free download is part of class 10 science notes for quick revision. The following chemical equation represents the reaction between hydrogen and chlorine to form hydrogen chloride. Chemical equilibrium calculations 12 may 2015 section a. Equilibrium is the state of a process in which the properties like temperature, pressure, and concentration etc of the system do not show any change with passage of time. Equilibrium is all about balance and today hank discusses chemical equilibrium, concentration, temperature, and pressure. Weak acids, weak bases, and buffers are systems in equilibrium. It is dynamic because both the forward and reverse reactions continue to occur. Equilibrium can be determined as the point when the rates of the forward and reverse reactions are equal, or when the concentrations of the reactants and products becomes constant. A chemical equilibrium on the other hand is when a reaction goes in the forward and backward reaction at the. Many chemical reactions do not go to completion but instead attain a state of chemical equilibrium. Aside from introducing the meaning of values, this section will require the learners to calculate equilibrium constants from known concentrations, as well as to calculate the concentrations of reactants and products. In this live gr 12 physical sciences show we take a look at chemical equilibrium calculations. In this chapter learners will explore the concept of chemical equilibrium in detail.
Chemical reactions and equations class 10 notes science. Science chemistry 12 elaborations british columbia. Le chateliers principle helps to predict what effect a change in temperature, concentration or pressure will have on the position of the equilibrium in a chemical reaction. While a reaction is in equilibrium the concentration of the reactants and products are constant. Chemical equilibrium is the state of a reversible reaction where the rate of the forward reaction equals the rate of the reverse reaction. The strength of an acid or base depends on the degree of dissociation of its ions. Equilibrium and le chateliers principle experiment. The equilibrium constant is used to determine whether reactants or products are favoured in a reaction at chemical equilibrium. Law of chemical equilibrium, equilibrium constant examples. Where to download mind the gap physical science study guide grade 12 mind the gap physical science study guide grade 12. Chemistry 12 tutorial 2 enthalpy and entropy chemistry. In this section we will be talking about the basics of acids and bases and how acidbase chemistry is related to chemical equilibrium.
A state in which the rates of the forward and reverse reactions are equal and the concentrations of the reactants and products remain constant. Consolidation exercises organic molecules and their reactions consolidation exercises rates, chemical equilibrium and electrochemistry 1. The lecture handouts are available in the table below. A survey of soil chemistry literature shows that the concept of chemical speciation has gained acceptance as a useful tool to interpret complex soil interactions. If such a stress is applied, the reversible reaction will undergo a shift in order to reestablish its equilibrium. Word equations write the word equations below as chemical equations and balance. Multiple choice 23 marks total use the answer sheet found at the end of this examination to answer the multiple. Alternatively, use the equilibrium system in periods of low humidity, the colour of the weather indicator is blue. Plan your 60minute lesson in science or chemistry with helpful tips from raymond stadt. Now lets assume that you have been transferred to the division responsible for the. A chemical reaction achieves chemical equilibrium when the rate of forward reaction and that of the reverse reaction is same. Chemistry grade 12 year term 1 content curriculum statement rates of reactions revised chemical equilibrium chemical equilibrium and factors affecting equilibrium.
Revision notes on chemical and ionic equilibrium equilibrium. When the humidity is high, the products will be favoured and the colour of the indicator will be pink. Equilibrium constants can also be expressed in terms of pressure. Revision notes on chemical and ionic equilibrium askiitians. The value of the equilibrium constant will vary with temperature.
Here, we will do a bunch of practice problems for balancing chemical equations. We will cover acid and base definitions, ph, acidbase equilibria, acidbase properties of salts, and the ph of salt solutions. The reaction which does not undergo an equilibrium shift when only the volume is changed. Chemistry 12 unit 2 chemical equilibrium tutorial 6 calculations involving the equilibrium constant page 1. Examples of stresses include increasing or decreasing chemical concentrations, or temperature changes. Strategies used by grade 12 physical sciences students in solving chemical equilibrium problems article pdf available june 2018 with 862 reads how we measure reads. A reversible reaction at equilibrium can be disturbed if a stress is applied to it. In this sense a steady state is a dynamic equilibrium.
According to new cbse exam pattern, mcq questions for class 10 science pdf carries 20 marks. Increasing the rate of the forward reaction will mean an increase in products. Demonstrationanimation demonstrate a chemical equilibrium with an no 2tn 2o 4system or a cocl 4. For example, in a cluster of crystals of solute in contact with a saturated solution, the small crystals get smaller as the large crystals grow. Electricity grade 11 revision electrodynamics motors and generators and alternating current. Chemical equilibrium exercises chemistry libretexts. Shade in the circle that corresponds to your answer. In this lesson we discuss dynamic equilibrium as well as discuss equilibrium.