Question

Define reaction quotient.

Answer 1

It is a type of quantity that provides the measurement related with the reactants and products of the reaction with well-defined overall stoichiometry.

Complete answer:
In chemical thermodynamics, the reaction quotient, denoted by ${Q_r}$ or $Q$ is a quantity that provides a measurement of the relative quantities of products and reactants present in a reaction mixture for a reaction with well-defined overall stoichiometry, at a particular point in time. Mathematically, it is characterized as the proportion of the exercises (or molar concentrations) of the product species over those of the reactant species engaged with the compound reaction, considering stoichiometric coefficients of the response as types of the fixations. In equilibrium, the reaction quotient is consistent over the long run and is equivalent to the equilibrium constant.
In the extraordinary case that the reaction is at equilibrium the reaction quotient is consistent and equivalent to the equilibrium constant that shows up in the outflow of the law.
Equilibrium constant is denoted by $K$ . The main difference between $K$ and $Q$ is that $K$ describes a reaction that is at equilibrium, whereas $Q$ describes a reaction that is not at equilibrium. To determine $Q$ , the concentrations of the reactants and products must be known. For a given general chemical equation:
$aA + bB \rightleftharpoons cC + dD$
The $Q$ equation is written by multiplying the activities (which are approximated by concentrations) for the species of the products and dividing by the activities of the reactants. In the event that any part in the reaction has a coefficient, shown above with lower case letters, the fixation is raised to the intensity of the coefficient. QQ for the above condition is in this way:
${Q_c} = \dfrac{{{{[C]}^c}{{[D]}^d}}}{{{{[A]}^a}{{[B]}^b}}}$

Note: This condition just shows parts in the vaporous or watery states. Each unadulterated fluid or strong has a movement of one and can be practically precluded. Harmony constants truly contain a proportion of fixations (real focus partitioned by the reference fixation that characterizes the standard state). Since the standard state for focus is typically picked to be $1\,mol\,{l^{ - 1}}$ , it isn't worked out in reasonable applications. Henceforth, the proportion doesn't contain units.