Hydrogen sulfite ion

The reaction of the hydrogen sulfite ion in an alkaline solution with ketones and aldehydes is ... 

Only with large cations such as Rb, Cs and NRafR = Et, Bu", n-pentyl) has it proved possible to isolate the. solid sulfites The sulfite ion SOs is pyramidal with Cj,. symmetry angle O-S-O 106°, S-O 151 pm. The hydrogen sulfite ion also appears to have C3, symmetry both in the solid state and in solution, i.e. protonation occurs at S rather than... 

L.21 Thiosulfate ions (S,0,2-) disproportionate in acidic solution to give solid sulfur (S) and hydrogen sulfite ion (HSO ) ... 

Write the Lewis structure, including typical contributions to the resonance structure (where appropriate, allow for the possibility of octet expansion, including double bonds in different positions), for (a) sulfite ion (b) hydrogen sulfite ion (c) perchlorate ion (d) nitrite ion. 

The hydrogen sulfite ion, HSO3-, is amphoteric. Write chemical equations to show how it acts first as an acid and then as a base. 

Sodium hydrogen sulfite, NaHS03, is a preservative that is used to prevent the discolouration of dried fruit. In aqueous solution, the hydrogen sulfite ion can act as either an acid or a base. Predict whether NaHSOs dissolves to form an acidic solution or a basic solution. (Refer to Appendix E for ionization data.)... 

Several carbonyl additions have characteristics similar to those of cyanohydrin formation. A typical example is the addition of sodium hydrogen sulfite, which proceeds readily with good conversion in aqueous solution with most aldehydes, methyl ketones, and unhindered cyclic ketones to form a carbon-sulfur bond. No catalyst is required because sulfite is an efficient nucleophilic agent. The addition step evidently involves the sulfite ion—not hydrogen sulfite ion ... 

Dissolved in water, sulfur dioxide produces sulfurous acid (H2S03), hydrogen sulfite ion (HSOj), and sulfite ion (SOf ). Sodium sulfite (Na2S03) has been used as a chemical food preservative, although some individuals are hypersensitive to it. 

For the determination of the unknown quantities in the liquid film, three further secondary conditions are needed. So, it is necessary to divide the molar masses of the sulfur and the calcium resulting from the mass balances in the film. A sulfur atom is bonded in hydrogen sulfite ion, molecular diluted sulfur dioxide, sulfite ion and calcium sulfite hemihydrate... 

Fig. 2-29. Formation of a-hydroxysulfonic acids after addition of hydrogen sulfite ions to aldoses. R = the monosaccharide residue.

It follows from these equilibria that the relative concentrations of sulfur dioxide, hydrogen sulfite, and sulfite are governed by the pH of the solution (Fig. 7-1). As can be seen, sulfur dioxide is present almost exclusively in the form of hydrogen sulfite ions at pH around 4. Below and above this value the concentrations of sulfur dioxide and sulfite ions, respectively, are successively increased. These equilibria also vary with the temperature. At temperatures used for pulping (130°-170°C), the actual pH value is higher than that... 

Fig. 7-1. The molar ratio of hydrogen sulfite ion concentration to total sulfur dioxide as a...

The monosaccharides formed during pulping are not completely stable. About 10-20% of them are oxidized to aldonic acids by hydrogen sulfite ions. Simultaneously, hydrogen sulfite is reduced to thiosulfate ... 

A considerable part of the hydrogen sulfite ions is consumed in reactions other than the sulfonation of lignin. In the absence of wood, sulfur dioxide solutions are decomposed at elevated temperatures according to the equation ... 

The hydrogen sulfite ion, HSO3, is a weak acid in aqueous solution. Write an equation showing the equilibrium established when hydrogen sulfite is dissolved in aqueous solution, using unequal arrows to show the equilibrium. 

Thiosulfate ion (8203 ) disproportionates in acidic solution to give solid sulfur and aqueous hydrogen sulfite ion (HSO3). Write a balanced equation for this reaction. 

HS03(i3<3 ) (hydrogen sulfite ion) is then slowly oxidized by oxygen that is also dissolved in the droplets ... 

A key step in the formation of sulfuric acid from dissolved SO2 in acid precipitation is the oxidation of hydrogen sulfite ion by hydrogen peroxide ... 

Iodine is however also reduced very rapidly by hydrogen sulfite ions to iodide ions ... 

Although sodium thiosulfate solutions are resistant to air oxidation, they do tend to deeompose to give sulfur and hydrogen sulfite ion ... 

HjSOjt sulfurous acid IHSO, LSO32- hydrogen sulfite ion sulfite ion... 

An amphoteric substance is one that may act as either an acid or a base. The hydrogen sulfite ion is amphoteric. Write reactions that demonstrate this property of HSOj . 

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