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Self-ionization constant of water

Recall that an equilibrium-constant expression relates the concentrations of species involved in an equilibrium. The relationship for the water equilibrium is simply [H30" ][0H ] = K q. This equilibrium constant, called the self-ionization constant of water, is so important that it has a special symbol, Its value can be found from the known concentrations of the hydronium and hydroxide ions in pure water, as follows ... [Pg.558]

The value of Kv>, at STP is 1.0x10 ". The self-ionization constant of water, Ky, is thus just a special case of an acid dissociation constant. [Pg.110]

Water itself is neutral. It forms an equal number of hydronium and hydroxide ions by self-dissociation. The process is described by the equilibrium constant K, the self-ionization constant of water. At 25°C,... [Pg.60]

Kv is the self-ionization constant for water (Table 3.2) and equation (3.18) reflects the not surprising inverse relation between Ka and Kh. It is only when Ka and Kv for a compound are of different magnitudes that it may be classified as an acid or a base. An example which is difficult to classify is hypoiodous acid (HOI) where K = 2.5 x lO11 mol dm 3 andKh = 3.2 x 10 10 mol dm3. Although Kb has been widely used in the past, it is a quantity which is largely redundant, for Ka (or pKa) may be used to express the strength of bases as well as acids, see Table 3.3. [Pg.35]

Km is the self ionization constant for water (table 3.2) and equation (3. f8) reflects the not surprising inverse relation between Kt and Kh. It is only when AT, and Kh for a compound are of different magnitudes that it may be classified as an acid or base. An example which is difficult to classify is... [Pg.44]

The activity of the solvent molecule HS in a single-component solvent is constant and is included in Kus. The concentration of ions is mostly quite low. For example, self-ionization occurs in water according to the equation 2H20— H30+ + OH". The conductivity of pure water at 18°C is only 3.8 X 10"8 Q"1 cm-1, yielding a degree of self-ionization of 1.4xl0"19. Thus, one H30+ or OH" ion is present for every 7.2 x 108 molecules of water. Some values of Kus are listed in Table 1.5 and the temperature dependence of the ion product of water Kw is given in Table 1.6. [Pg.58]

Some ionizing solvents are of major importance in analytical chemistry whilst others are of peripheral interest. A useful subdivision is into protonic solvents such as water and the common acids, or non-protonic solvents which do not have protons available. Typical of the latter subgroup would be sulphur dioxide and bromine trifluoride. Non-protonic ionizing solvents have little application in chemical analysis and subsequent discussions will be restricted to protonic solvents. Ionizing solvents have one property in common, self-ionization, which reflects their ability to produce ionization of a solute some typical examples are given in table 3.2. Equilibrium constants for these reactions are known as self-ionization constants. [Pg.42]

Water itself is ionized to a very small extent (equation 6.1) and the value of the self-ionization constant, (equation 6.2), shows that the equilibrium lies well to the left-hand side. The self-ionization in equation 6.1 is also called autoprotolysis. [Pg.163]

The resulting equilibrium constant is called the ionization constant, or dissociation constant, or self-ionization constant, or ion product of water, and is symbolized byAfw... [Pg.64]

These two constants are related by the self-ionization or autoprotolysis constant of water. Consider the ionization of water ... [Pg.20]

Using the equilibrium expression that you reviewed in Chapter 13, the equilibrium constant for the self-ionization of water can be expressed as ... [Pg.320]

The second variation is to determine either the pH or the hydrogen ion concentration of a solution when given the hydroxide ion concentration, [OH-], for the solution. To solve these problems you need to utilize the equilibrium constant expression for the self-ionization of water (Kw). This expression will allow you to convert from the hydroxide ion concentration, [OH-], to the hydrogen ion concentration, [H+], The [H+] can then be used to calculate pH if necessary. One of the free-response questions on the 1999 test required this calculation. [Pg.322]


See other pages where Self-ionization constant of water is mentioned: [Pg.202]    [Pg.557]    [Pg.558]    [Pg.558]    [Pg.559]    [Pg.583]    [Pg.924]    [Pg.243]    [Pg.317]    [Pg.318]    [Pg.202]    [Pg.164]    [Pg.188]    [Pg.866]    [Pg.182]    [Pg.208]    [Pg.1002]    [Pg.208]    [Pg.236]    [Pg.1113]    [Pg.5]    [Pg.202]    [Pg.557]    [Pg.558]    [Pg.558]    [Pg.559]    [Pg.583]    [Pg.924]    [Pg.243]    [Pg.317]    [Pg.318]    [Pg.202]    [Pg.164]    [Pg.188]    [Pg.866]    [Pg.182]    [Pg.208]    [Pg.1002]    [Pg.208]    [Pg.236]    [Pg.1113]    [Pg.5]    [Pg.3043]    [Pg.27]    [Pg.3042]    [Pg.21]    [Pg.30]    [Pg.60]    [Pg.394]    [Pg.67]    [Pg.258]    [Pg.578]    [Pg.222]   
See also in sourсe #XX -- [ Pg.20 ]




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Constants self-ionization

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Ionization constant constants

Ionization constant of water

Ionization constant, water

Ionization of water

Self-ionization

Self-ionization constant water

Self-ionization of water

Water constant

Water ionization

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