Sodium methanoate

Goldschmidt process The preparation of sodium methanoate by pressurizing CO and... 

Crystallizes from water in large colourless prisms containing 2H2O. It is poisonous, causing paralysis of the nervous system m.p. 101 C (hydrate), 189°C (anhydrous), sublimes 157°C. It occurs as the free acid in beet leaves, and as potassium hydrogen oxalate in wood sorrel and rhubarb. Commercially, oxalic acid is made from sodium methanoate. This is obtained from anhydrous NaOH with CO at 150-200°C and 7-10 atm. At lower pressure sodium oxalate formed from the sodium salt the acid is readily liberated by sulphuric acid. Oxalic acid is also obtained as a by-product in the manufacture of citric acid and by the oxidation of carbohydrates with nitric acid in presence of V2O5. 

Although carbon monoxide appears to be the anhydride of methanoic acid it does not react with water to give the acid however, it will react with sodium hydroxide solution above 450 K, under pressure, to give sodium methanoate ... 

Sodium methanoate, NaHCOO, and methanoic acid, HCOOH, can be used to make a buffer solution. Explain how this combination resists changes in pH when small amounts of acid or base are added. 

When 400 cm of 0-010 mol 1" methanoic acid is added to 100 cm of 0-050 mol 1" sodium methanoate, both solutions will effectively have been diluted up to 500 cm and their concentrations change as follows ... 

Explain how a mixture of solutions of methanoic acid and sodium methanoate act as a buffer when small quantities of (a) HCl(aq) or (b) NaOH(aq) are added. 

Attack at the carbonyl group with formation of the intense green-yellow fluorescent anion 188a R = CH(CH3)2 occurs, for example, if sodium methano-late in benzene/methanol is used. In contrast, methyl magnesium bromide in... 

Write a mechanism for the oxidation of sodium methanoate (formate) to carbon dioxide by potassium permanganate which is consistent with the following facts ... 

We can use pKa to predict what happens if we react an acyl chloride with a carboxylate salt. We expect the carboxylate salt (here, sodium formate, or sodium methanoate, HCC Na) to act as the nucleophile to form a tetrahedral intermediate, which could collapse in any one of three ways. 

In the absence of a laboratory or industrial pressure vessel, catalytic hydrogentransfer is a viable alternative. Here, the nitro compound is stirred in a solvent with a catalyst, commonly 1% platinum on carbon, in the presence of a hydrogen donor such as hydrazine, sodium formate (sodium methanoate) or methylcyclohexene (Scheme 7.6). In the case of hydrazine, interaction at the catalyst surface produces the reductant, hydrogen, and nitrogen. Toluene is the by-product when methylcyclohexene is used. 

In contrast, the salt formed by the neutralisation of methanoic acid, HCOOH(aq), with NaOH(aq) gives a basic solution with the pH dependent on the concentration of the salt. Sodium methanoate is the salt of a weak acid and strong base, and in the solid consists of Na and HCOO ions. When dissolved in water, Na" "(aq) ions show no acid/base behaviour with the water since NaOH(aq) is a strong base consisting of Na" (aq) ions and OH (aq) ions only. However, HCOO (aq) is the conjugate base of the weak acid HCOOH(aq), and will thus accept a proton from the solvent water to form the undissociated acid HCOOH(aq) in the... 

Carbon monoxide is neutral and only sparingly soluble in water. It is not the anhydride of methanoic acid, although under extreme conditions it can react with sodium hydroxide to form sodium methanoate. It forms metal carbonyls with transition metals, and its toxicity is due to its ability to form a complex with hemoglobin. 

Catalysts speed up chemical reactions in which they do not actually enter. They are typically used in small quantities. Raney nickel is used as a catalyst in hydrogenation of oils and sodium methoxide (sodium methanoate) in the transesterification of fats. Acids are used as catalysts in the production of certain modified starches. Catalysts also include the enzymes used as food additives, such as amylase (El 100), proteases (El 101, for example papain, bromelain and ficin), glucose oxidase (El 102), invertase (E1103) and lipases (El 104). 

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