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Acid strength classifying

Since the hydrogen-element bond energy decreases from sulphur to tellurium they are stronger acids than hydrogen sulphide in aqueous solution but are still classified as weak acids—similar change in acid strength is observed for Group Vll hydrides. [Pg.284]

The several attempts, published in the literature, to describe the kinetics of vapour phase olefin (mostly ethylene) hydration can be classified into two groups according to the basic model used. One model, for reactions catalysed by phosphoric acid supported on solids, treats the kinetics as if the process were homogeneous acid catalysis and takes into account the acid strength of the supported acid. Thus, a semiempirical equation for the initial reaction rate [288]... [Pg.324]

The term acid is derived from the Latin word acidus meaning sour. Arrhenius (1859-1927) of Sweden introduced the idea of compounds splitting into their constituent ions. Based on this idea, he was able to explain that the concentration of the hydrogen ions in water (aqueous solution) determined the strength of an acid. Arrhenius was awarded the Nobel Prize in 1903 for his work on ionization. Acids are classified as naturally occurring acids and mineral acids. [Pg.52]

Acidity and acid strength distribution were evaluated by temperature-programmed desorption of ammonia. The acid sites were classified as weak < 300°C, medium (M) 300 < T < 450° 0 and strong (S) 450 < T < 550° 0. Ultra strong acid sites (S in a. u ) are defined as a ratio of peak height for catalyst to alumina (Ni cat./AfjOj) at 550° C,... [Pg.562]

Suitable catalysts for cationic polymerization may be conveniently classified into three groups. The classic protonic mineral acids, such as H2SO4, HCIO4, and H3PO4, are often useful. Effective catalysis is obtained if the acid selected has high acid strength, and an anion of low nucleophilicity (Eq. 22.9). [Pg.722]

Acids and bases are essential substances in home, industry, and the environment. In aqueous solution, water combines with the proton released from an acid to form the hydrated species represented by HgO laq). In the Arrhenius definition, acids contain H and yield HaO in water, bases contain OH and yield OH in water, and an acid-base reaction (neutralization) is the reaction of and OH to form HgO. Acid strength depends on [HaO" ] relative to [HA] in aqueous solution. Strong acids dissociate completely and weak acids slightly. The extent of dissociation is expressed by the acid-dissociation constant, K. Weak acids have values ranging from about 10 to 10 . Many acids and bases can be classified qualitatively as strong or weak based on their formulas. [Pg.582]

Acid Strength of Solid Catalysts. Breinsted Centres. - There are many possibilities for classifying solid BreSnsted acids. From the acidity origin point of view one can divide these catalysts into following groups ... [Pg.116]

Bronsted [Br 23, Br 28, Br 30] classified solvents according to their proton donor and proton acceptor capability, on the basis of three of their properties relative permittivity, acid strength and basic strength thus he distinguished between the following eight fundamental solvent classes ... [Pg.20]

Understand the nature of the hydrated proton, the Arrhenius definition of an acid and a base, and why all strong acid-strong base reactions have the same A// xn describe how acid strength is expressed by K, classify strong and weak adds and bases from their formulas ( 18.1) (SP 18.1) (EPs 18.1-18.12)... [Pg.609]

Once acids and bases have been classified as hard or soft, a simple rule can be given hard acids prefer to bond to hard bases, and soft acids prefer to bond to soft bases (the HSAB principle)P The rule has nothing to do with acid or base strength but merely says that the product A—B will have extra stability if both A and B are hard or if both are soft. Another rule is that a soft Lewis acid and a soft Lewis base... [Pg.341]

EXAMPLE 20.2. Classify the following acids and bases according to their strength HC1, HC2H,02, NaOH. and NH v... [Pg.303]

As we have seen, the Lewis theory of acid-base interactions based on electron pair donation and acceptance applies to many types of species. As a result, the electronic theory of acids and bases pervades the whole of chemistry. Because the formation of metal complexes represents one type of Lewis acid-base interaction, it was in that area that evidence of the principle that species of similar electronic character interact best was first noted. As early as the 1950s, Ahrland, Chatt, and Davies had classified metals as belonging to class A if they formed more stable complexes with the first element in the periodic group or to class B if they formed more stable complexes with the heavier elements in that group. This means that metals are classified as A or B based on the electronic character of the donor atom they prefer to bond to. The donor strength of the ligands is determined by the stability of the complexes they form with metals. This behavior is summarized in the following table. [Pg.313]

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]

An ion that does not react with water has no effect on the pH of water. If both the cation and the anion in a salt do not react with water, a solution of the salt will be neutral. Which salt consists of cations and anions that do not react with water How did you classify this salt in terms of the strength of the acid and base used to form it ... [Pg.420]

Classify your unknown salt in terms of the strength of the base and the acid from which the salt was formed. [Pg.420]


See other pages where Acid strength classifying is mentioned: [Pg.46]    [Pg.79]    [Pg.64]    [Pg.680]    [Pg.3395]    [Pg.263]    [Pg.898]    [Pg.798]    [Pg.3394]    [Pg.5553]    [Pg.316]    [Pg.75]    [Pg.293]    [Pg.609]    [Pg.929]    [Pg.226]    [Pg.444]    [Pg.502]    [Pg.80]    [Pg.586]    [Pg.121]    [Pg.303]    [Pg.437]    [Pg.293]    [Pg.15]    [Pg.233]    [Pg.123]    [Pg.281]    [Pg.145]    [Pg.30]    [Pg.113]    [Pg.42]   
See also in sourсe #XX -- [ Pg.581 ]

See also in sourсe #XX -- [ Pg.581 ]

See also in sourсe #XX -- [ Pg.583 ]




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