New answers tagged

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Generally, the process of turning $\ce{HX}$ into $\ce{H+}$ and $\ce{X^-}$ can be broken into 2 hypothetical steps [...] Indeed, this process is slightly simplified because acidities are typically measured in solution, whereas your thermodynamic cycle only deals with gas-phase energetics. However, in the present case, it's actually enough to look at gas-...


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Here is a bigger chunk of the periodic table with acid dissociation constants of the hydrides: Source: Libretexts The authors claim that the two factors are electronegativity (how much of a positive partial charge the hydrogen has in the covalent bond) and bond strength (expressed as estimated homolytic cleavage energy). There is no strong anomaly for the ...


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The sum of the $\mathrm{p}K_\mathrm{b}$ value of a base and the $\mathrm{p}K_\mathrm{a}$ value of its conjugate acid is a constant (at a constant temperature), and is equal to $\mathrm{p}K_\mathrm{w}$ (which is $14$ at room temperature). The more stable the conjugate acid, the higher the $\mathrm{p}K_\mathrm{a}$ of the conjugate acid $\implies$ lower $\...


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Meeting the condition you set is likely imposssible. There are multiple approaches how to define an acid, and a base. Despite differences between them, there are some which are related to each other. For Brønsted and Lowry, a base is capable to attract and bind a proton; this already is an extension (mathematically speaking, a superset) of Arrhenius' focus ...


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Hydrogen atoms need not bevunalterqbly acidic or non-acid for all time. Chemical reactions elsewhere is a molecule can change a hydrogen atoms acid-base reactivity Suppose you were to react acetoacetic acid, $\ce{CH3-CO-\color{blue}{CH2}-CO-OH}$, with a strong base such as a Grignard reagent. The base extracts the catboxyl proton, and that's it. In the ...


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From my answer: The IUPAC goldbook states that: "pyro" is used as a prefix designating compounds formed by heating a compound, usually with the elimination of water, carbon dioxide, or other simple molecule, e.g. pyroglutamic acid from glutamic acid. Since Pyroboric acid is made by heating boric acid, it is prefixed as pyro. You can also call it ...


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If there are arrows going both ways then that means it’s in equilibrium between the right side (products) and the left side (reactants). It doesn’t mean that water is a mix of H3O+ and -OH, a vast majority of water will stay H2O, and the small amount of H3O+ or -OH wouldn’t be anywhere near a concentration to hurt you I think the purpose of that was to show ...


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When we say that a metal falls below hydrogen in the electrochemical series, we typically refer to the oxidizing power of hydrogen ion at 1 molar concentration in water solution. The oxidizing power of concentrated sulfuric acid, forming sulfur dioxide and water when it reacts, could be greater than that of the aqueous hydrogen ions; if so, then ...


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Essentially, you are trying to determine the conjugate acid of the borate anion. Yes, that approach is likely to fail with boric acid & borate anions. In fact if you want to form the conjugate acid of $\ce{RB(OH)3-}$ by protonation, instead of protonating the boron atom, you should protonate the oxygen atom, because that's the atom that possesses an ...


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I propose this simple graphic answer as a complement to the more thorough replies above (comments welcome to confirm validity of my answer). Trace pH Vs % [HA] and [A-]. 0% means you only have the acid [HA] and 100% you only have [A-]. Addition of acid or base, to the buffer solution, affects the ratio [A-]/[AH] and consequently, pH. This has been explained ...


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There are multiple definitions of acid and base. If one picks the one by Brønstedt and Lowry, than indeed the acid is the proton donor, the base the proton acceptor; and the transfer of the proton from the acid to the base is the neutralization reaction. However, e.g. hydrochloric acid isn't just water and $\ce{H+}$, and lye isn't only water and $\ce{OH^-}$....


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First off, based on acid strength carboxyl is not more electron-withdrawing in this setting than fluorine. From the respective WP articles on the compounds below, we find that carboxyl is actually about as electron-withdrawing as chlorine, with fluorine beating both. Name Formula $\mathrm{p}K_\mathrm{a}$ Chloroacetic acid $\ce{Cl{-}CH2COOH}$ 2.86 Malonic ...


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