Sodium bicarbonate citric acid neutralization

Three molecules of sodium bicarbonate are required to neutralize one molecule of citric acid, and two molecules of sodium bicarbonate to neutralize one molecule of tartaric acid. A specification for sodium bicarbonate is contained in the Food Chemicals Codex (FCC). 

Add about ° of a cup of the appropriate solution to each of the cups you have labeled. The fruit should not be completely submerged in the solutions, but make sure each slice of fruit gets completely coated with the solution. The vinegar and lemon juice solutions serve as acidic solutions (of acetic and citric acids, respectively). The baking soda and milk of magnesia solutions serve as basic solutions (of sodium bicarbonate and magnesium hydroxide, respectively), while the water serves as a neutral control solution. 

Nitrilotriacetlc acid was supplied by the Hampshire Chemical Co., Division of W. R. Grace Co., Nashua, New Hampshire. For feeding studies It was neutralized with 1 M sodium hydroxide to provide a 1% NTA solution. Ethyl nltrllotrlacetate was obtained as a clear colorless viscous oil by refluxing 30g of nltrllotrl-acetlc acid In 1 liter of absolute alcohol In the presence of 3g of toluenesulphonlc acid for forty-eight hours. The alcohol was removed by distillation from a water bath in vacuo, the residue mixed with 100 ml of 0.5 percent sodium bicarbonate solution and extracted with one liter of benzene. The benzene solution was extracted twice more with bicarbonate solution, washed with water and concentrated from a water bath In vacuo. The clear colorless residual oil was dissolved by shaking with an aqueous solution of 1.5 M citric acid and the volume adjusted by addition of distilled water to provide a final solution of 1% NTA ethyl ester as citric acid salt. 

The methods for the isolation of alkaloids are based upon the fact that they can be extracted under neutral or basic conditions (after basification of, e.g., the plant material or biofluid to pH 7-9 with ammonia, sodium carbonate, or sodium bicarbonate), as free base with organic solvents (e.g., dichloromethane, chloroform, ethers, ethyl acetate, alcohols) and as pro-tonated base with polar solvents (water, alcohols) under acidic conditions (after acidification to pH 2-4 with diluted acids like phosphoric acid, sulfuric acid, citric acid). Some alkaloids can only be extracted at higher pH (>10), e.g., tryptamine. On the other hand, alkaloids containing phenolic groups dissociate at higher pH, and are thus not extracted by organic solvents under such conditions (e.g., morphine). Further purification can be done by liquid/ liquid extraction or liquid/solid extraction. 

Both NaHCOs and Na2C03 are used as add neutralizers in acid spills. The bicarbonate or carbonate salt is added until the fizzing due to the formation of C02ig) stops. Sometimes sodium bicarbonate is used as an antacid to soothe an upset stomach. In that case the HCOs reacts with stomach acid to form CO2O ). The fizz when Alka-Seltzer tablets are added to water is due to the reaction of sodium bicarbonate and citric acid. 

Acids and bases are important substances in health, industry, and the environment. One of the most common characteristics of acids is their sour taste. Lemons and grapefruits are sour because they contain organic acids such as citric and ascorbic acid (vitamin C). Vinegar tastes sour because it contains acetic acid. We produce lactic acid in our muscles when we exercise. Acid from bacteria turns milk sour in the production of yogurt and cottage cheese. We have hydrochloric acid in our stomachs that helps us digest food. Sometimes we take antacids, which are bases such as sodium bicarbonate or milk of magnesia, to neutralize the effects of too much stomach acid. 

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