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	Reaction quotient, Qc and Qp (Site not responding. Last check: 2007-10-13)
		the reaction is not at equilibrium, and the forward reaction predominates till equilibrium is attained.
		the reaction is not at equilibrium, and the backward reaction predominates till equilibrium is attained.
		, 0.0230 moles of Cl Is the reaction at equilibrium?
	www.accd.edu /sac/chemistr/madappat/EQ_L3.htm (271 words)

	Reaction quotient - Wikipedia, the free encyclopedia
		And the expression for the reaction quotient is:
		The Reaction Quotient is taken at a particular instant, this is at a time before equilbrium is reached.
		This reaction quotient is directly related to the Law of Mass Action and the Le Chatelier Principle.
	en.wikipedia.org /wiki/Reaction_quotient (289 words)

	Chapter 13 Review
		Reaction then occurs to change the composition of the mixture until a new equilibrium is established.
		The equilibrium constant for an exothermic reaction decreases as the temperature increases.
		The equilibrium constant for an endothermic reaction increases as the temperature increases.
	www.msu.edu /~serordan/chap.13.htm (560 words)

	Lect. 10 (Site not responding. Last check: 2007-10-13)
		Rates of reactions have to be measured experimentally in order to determine the kinetic characteristics of the reaction.
		To determine the rate law for a particular reaction one carries out the reaction under controlled and constant conditions with the exception of varying the concentration of one or more of the reactants.
		Also, the rates are faster in the early stages of the reaction and become slower as the reaction proceeds.
	www.chemistry.ucsc.edu /teaching/Winter02/Chem1C/Lect.10.htm (1395 words)

	Rate Equilibrium (Site not responding. Last check: 2007-10-13)
		Since the reverse reaction occurs simultaneously with the forward reaction, a reaction at equilibrium may have reactants remaining.
		If the reaction quotient is less than the equilibrium constant, the concentrations of the products must increase and the reaction will proceed in the forward direction until equilibrium is restored.
		If the reaction quotient is more than the equilibrium constant, the concentration of the products must decrease and the reaction will run in the reverse direction until equilibrium is restored.
	www.scientia.org /cadonline/Chemistry/acidbase/rateequilib.ASP (560 words)

	Chemistry : Chapter 15 : Overview (Site not responding. Last check: 2007-10-13)
		The law of mass action states that any reaction mixture eventually reaches a state (equilibrium) in which the ratio of the concentration terms of the products to the reactants, each raised to a power corresponding to the stoichiometric coefficient for that substance in the balanced chemical equation, is a characteristic value for a given temperature.
		Therefore the equilibrium constant of the reverse reaction is the reciprocal of the equilibrium constant of the forward reaction.
		While the rate of the forward reaction is equal to the rate of the reverse reaction, equilibrium constant expressions are not a measurement of rate.
	www.wwnorton.com /chemistry/overview/ch15.htm (724 words)

	[No title] (Site not responding. Last check: 2007-10-13)
		The activated complex is the structure at the maximum energy point along the reaction path; the activation energy is the difference between the energies of the activated complex and the reactants.
		A reaction in which a fragment of one reactant is replaced by another reactant (or by a fragent of another reactant).
		For example, given a reaction A B, Hess's law says that H for the reaction is the same whether the reaction is written as A C B or as A B. This is the same as writing that H(A B) = H(A C) + H(C B).
	lacyg.box.sk /glos/chemical1 (19452 words)

	Equilibrium Expressions
		The equilibrium constant for this reaction is 0.030 at 250
		Because the reaction quotient for the intermediate conditions and the equilibrium constant are both relatively large, we can assume that the reaction doesn't have very far to go to reach equilibrium.
		for the reaction at this temperature is 0.040.
	chemed.chem.purdue.edu /genchem/topicreview/bp/ch16/equilib.html (4708 words)

	[No title]
		The reaction QUOTIENT, Q Given a set of starting concentrations for an equilibrium system, the question often arises whether these concentrations satisfy the equilibrium condition, and if not, in which direction (i.e., to the left, or to the right) will the reaction proceed in order to establish equilibrium.
		The reaction quotient tests given concentrations to learn whether or not they are equilibrium concentrations.
		For the reaction of carbon dioxide and hydrogen gases, to form carbon monoxide and water at 990 C, the equilibrium constant is 1.6.
	www.luc.edu /faculty/spavko1/c102/lect/3-feb.htm (1334 words)

	General Chemistry Online: Glossary:
		For example, the reaction quotient for A + B = C + D is equal to (C)(D) / ((A)(B)), where the parentheses indicate concentrations.
		The reaction quotient for A + 2B = 3C is equal to (C) For gas phase reactions, partial pressures
		The reaction rate is given as the instantaneous rate of change for any reactant or product, and is usually written as a derivative (e.
	antoine.frostburg.edu /chem/senese/101/glossary/r.shtml (838 words)

	Free Energy and Direction of Spontaneous Change
		If the proper quotient of concentrations at any given instant, the so-called reaction quotient, Q, is less that the equilibrium constant at that temperature, than the reaction will proceed forward in the direction the reaction is written.
		Reactions that proceed in the direction of the chemical driving 'force' are called spontaneous reactions.
		A reaction that has a positive change in entropy and a negative change in enthalpy will be strongly favored to proceed in the forward direction, i.e the reaction will have a very large equilibrium constant.
	itl.chem.ufl.edu /4411/2041/lec_u.html (622 words)

	Reaction Quotient (Site not responding. Last check: 2007-10-13)
		The Reaction Quotient (Q) expression of a reaction has the same equation as the equilibrium constant expression for that reaction.
		However, the reaction quotient is computed using the current concentrations or pressures, not the equilibrium ones.
		Solution: The reaction quotient is computed the same way the equilibrium constant is, just using the current pressures.
	www.cartage.org.lb /en/themes/Sciences/Chemistry/Miscellenous/Helpfile/Equilibrium/ReactionQuotient.htm (206 words)

	Chapters 15 and 16
		Use the reaction quotient, equilibrium constant and concentrations to predict if the reaction is at equilibrium or not, and to predict how the reaction will shift to reach equilibrium.
		Given a reaction, write the mass action expression for the reaction quotient and equilibrium constant.
		Given the equilibrium constant for a reaction, determine the equilibrium constant for the reverse reaction, or the reaction multiplied by an integer.
	virtual.yosemite.cc.ca.us /danielm/equilibrium_and_acid-base_equ_.htm (556 words)

	GIBBS FREE ENERGY (Site not responding. Last check: 2007-10-13)
		The balance between the contributions from the enthalpy and entropy terms to the free energy of a reaction depends on the temperature at which the reaction is run.
		When a reaction leaves the standard state because of a change in the ratio of the concentrations of the products to the reactants, we have to describe the system in terms of non-standard-state free energies of reaction.
		The contribution to the free energy of the reaction from the enthalpy term is therefore constant, but the contribution from the entropy term becomes smaller as the temperature is lowered.
	chemed.chem.purdue.edu /genchem/topicreview/bp/ch21/gibbs.html (2156 words)

	Chemical Sciences: Thermodynamics: Free Energy and Equilibrium Constants
		The equation linking free energy changes and the reaction quotient can be used to describe a reaction which is at chemical equilibrium.
		Most equilibria do not involve a reaction in which the states and amounts of reactants and of products are the same, and for these the numeric value of the constant will vary with the nominal unit chosen.
		C for the reaction of nitrogen and oxygen to form nitrogen monoxide in the gas phase, which is the oxidation of molecular nitrogen.
	www.psigate.ac.uk /newsite/reference/plambeck/chem2/p02061.htm (1514 words)

	[No title] (Site not responding. Last check: 2007-10-13)
		The reaction quotient, Q. Calculating Kc when all the concentrations of all the species present are known at equilibrium.
		K for the reverse reaction is the reciprocal of K for the forward reaction.
		Compare the value of the Reaction Quotient, Q, with the value of Kc Reaction Quotient has the same form as Kc but the values for the concentrations are not necessarily those at equilibrium.
	www.slcc.edu /schools/hum_sci/chemistry/faculty/iles/CHEM1220/unit2.htm (611 words)

	Dorlands Medical Dictionary
		caloric quotient, the quotient obtained by dividing the heat evolved (expressed in calories) by the oxygen consumed (expressed in milligrams) in a metabolic process.
		D quotient, the ratio of glucose to nitrogen in the urine.
		reaction quotient, for a balanced chemical equation, the product of the concentrations of the reaction products, each raised to the power equal to the coefficient of the product in the equation, divided by the concentrations of the reactants, each raised to the power equal to its coefficient.
	www.mercksource.com /pp/us/cns/cns_hl_dorlands.jspzQzpgzEzzSzppdocszSzuszSzcommonzSzdorlandszSzdorlandzSzdmd_q_01zPzhtm (2658 words)

	[No title] (Site not responding. Last check: 2007-10-13)
		Calculating the reaction quotient is the main focus of this document.
		Tutorial focuses on reaction quotient, which is computed using the current concentrations or pressures.
		This discussion Gary L. Bertrand, University of Missouri-Rolla focuses on the difference between the reaction quotient and the equilibrium constant.
	www.pearsoncustom.com /allpages/reactionquotient_bot.html (142 words)

	The Nernst equation
		The expression for the reaction quotient Q is
		The silver-chloride solution is not in its standard state, and the reaction is not in equilibrium.
		In order to use it, we need the reaction quotient, which can be computed from the initial concentrations given in the problem and the standard cell potential.
	www.nyu.edu /classes/tuckerman/honors.chem/lectures/lecture_26/node4.html (650 words)

	CHEMISTRY 125 - Lab 19: Explanation of H2O Effect on Equilibrium
		When you increase the pressure on a reaction the reaction shifts in the direction of fewer moles of gas.
		Pressure changes have no effect if there is no change in the number of moles of gas in the reaction (the numerator and denominator in K have the same form, i.e., overall powers).
		O you increase the concentrations of everything and the reaction shifts in the direction of fewer moles of aqueous substances.
	www.chemistry.ohio-state.edu /~rzellmer/chem125/lab/equil.htm (514 words)

	Gibbs Free Energy (Site not responding. Last check: 2007-10-13)
		The relationship between reaction spontaneity, entropy and enthalpy is given by the Gibbs free energy function.
		Since the Gibbs free energy is negatively related to the total entropy change, reactions that proceed in the direction of increasing entropy proceed in the direction of decreasing free energy (proceed such that less of the system is ordered).
		The equilibrium of the reaction occurs at the minimum of the curve (at which point the slope is horizontal).
	www.scientia.org /cadonline/Chemistry/thermochemistry/gibbs.ASP (364 words)

	Syllabi 2005-2006 B-KUL-G0N01A Fundamentals for Chemistry
		Structure and bonding in molecules are related to the organisation of matter in gaseous, liquid or solid state, and to chemical reactions.
		Reaction mechanisms PART D. The reversibility of chemical reactions, the dynamic equilibrium D.2.
		Calculating with the balance constant Kev, the reaction quotient Q and the conversion degree a.
	www.kuleuven.ac.be /onderwijs/aanbod/syllabi/G0N01AE.htm (633 words)

	[No title]
		An example of this type of reaction is the incomplete ionization of a weak acid, such as acetic acid, in water: CH3COOH + H2O == H3O+ + CH3COO- When the rate of forward reaction is equal to the rate of the reverse reaction, the system is said to be at equilibrium.
		The extent to which a reaction proceeds before reaching equilibrium is given by the equilibrium constant, K. A reaction at equilibrium can be disturbed when the reaction is subjected to stress, such as change in temperature, pressure or concentration of the chemical species.
		For exothermic reactions, (Ho is negative, so (-(Ho/R) increases K. At higher temperatures, 1/T decreases this positive contribution to K. A smaller K means a lower [products]equilibrium, in agreement with the prediction by Le Chatelier’s Principle.
	home.ku.edu.tr /~ldemirel/exp3.doc (1190 words)

	CHP - Reaction Quotient (Site not responding. Last check: 2007-10-13)
		The expression for the reaction quotient, Q, is the same as the expression for the equilibrium constant (see II-2.), but for partial pressures or concentrations of the reactants and products before the system reaches equilibrium.
		If Q < K then the reaction is proceeding in the forward direction.
		If Q > K then the reaction is proceeding in the reverse direction.
	www.chem.vt.edu /chem-ed/courses/equil/intro/reactquo.html (107 words)

	Chemistry 104 Study Groups--Equilibrium
		Understanding the formulation and meaning of the reaction quotient is critical for much of the material this semester.
		Students often are confused between the reaction quotient and the equilibrium constant.
		When the numerical value of the reaction quotient is equal to the numerical value of the equilibrium constant the reaction is at equilibrium.
	www.brynmawr.edu /Acads/Chem/Chem104lc/study/Equilibrium.html (346 words)

	Lecture Notes: Equilibrium Part II (Site not responding. Last check: 2007-10-13)
		is determined using the equilibrium concentrations of the reactants/products; the reaction quotient (Q) is calculated using the equilibrium constant expression and the initial concentrations (rather than the equilibrium concentrations)
		If the reaction quotient is greater than the value of K
		Note: some notes regarding the reaction quotient (Q) are included on this page in an unprintable section, you are not responsible for these notes.
	kaffee.netfirms.com /Chem/Lecture.Equilibrium2.html (625 words)

	Zum13
		The reaction quotient will, therefore, equal the equilbrium constant when the reaction has reached equilbrium.
		Since the stoichiometry of both reactions are the same, once the reactions have reched equilbrium, there will be no difference in the composition of the mixtures in the two flasks.
		C both the forward and reverse reactions must be slow, which reflects that very strong bonds are being broken and that the activiation energy is high.
	www.chem.ucalgary.ca /courses/203/Zum13.htm (1160 words)

	Reaction Table - EQUILIBRIA
		An equilibrium reaction in the gas phase must occur in a closed (constant volume) container.
		In order to apply the correct signs in the "Change" row, it is necessary to determine which direction the reversible reaction will proceed to reach equilibrium from its intial conditions.
		This is discovered by computing the initial reaction quotient, using initial concentrations (or partial pressures) from the first row of the Reaction Table:
	wb.chem.lsu.edu /htdocs/people/sfwatkins/MERLOT/rt/07equilibria.html (371 words)

	Reaction Quotient (Site not responding. Last check: 2007-10-13)
		Now you will learn about the reaction quotient and how to compare its numerical value with that of the equilibrium constant so that you can predict if the reaction is at equilibrium, shifting to the right, or shifting to the left.
		The reaction quotient is written in exactly the same way, but the concentrations are not necessarily the equilibrium values.
		, then the numerator is larger than it will be at equilibrium, which means that the reaction is in the process of shifting toward the reactants.
	erkki.kennesaw.edu /GCII5/gc00003.htm (260 words)

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