Effect on Ph of Perservatives

Introduction:

The purpose of the following experiment, The Effect of pH on a Preservative was to identify if the compound sodium benzoate becomes a new substance when coming in contact with acid (pH: 1-3). This is an essential procedure since our stomach is acidic. The reason why sodium benzoate is used as a food preservative is because of its low cost. (Unknown, KEMI) In addition, the density of an unknown liquid is calculated with the aid of a graph. The slope of the graph is the density.

This experiment has an impact in your life's, thus it is important to obtain accurate results in order to avoid any harm. Therefore, one must be certain; that all the glassware that are being used during the research are well cleaned and dried. This is crucial. Any traces of other substances that are present in the glassware can have a serious effect on our results, and furthermore one might come to a different conclusion. Consequently, the first step in this experiment is to clean all the glassware that are being utilized.

Expanding on the above-mentioned importance of accuracy, the method of keeping the results at a low error margin is quantitative transfers. This method is straightforward and simple. After transferring a product from a beaker or an other container, one must rinse it and transfer it again. This must be done over and over again until one is sure that absolutely no traces are left and that the entire product has been successfully transferred. This method is critical for acquiring high yields.

Continuing on the same subject, Vacuum Filtration method enables us to "isolate a solid from a liquid-solid mixture and removing solid impurities from a relative large quantity of liquid" (Lehman, p. 629). This method allows us to create a solid, with close to a 100% purity. This is critical, as we want to eliminate all the other chemicals that are attached to it in order to keep our results accurate. Hence, vacuum filtration must be applied.

Acid-Base Reaction is a reaction where one substance accepts an H+ proton (Bronston base ) and the other donates an H+ proton ( Bronston acid). This concept creates a new substance. In this experiment, the acid-base reaction between sodium benzoate and 3M of hydrochloric acid creates a new product called benzoic acid. The sodium benzoate was the base and HCl was the acid. The reaction mechanism will be illustrated later.

Washing and Drying solid is significant as after acquiring the solid through vacuum filtration one mask sure that no volatile substances are left. Thus, after the solid has been collected one must place it onto a watch glass and place it into an oven. In order to be certain when to take out the solid from the oven, one must always weigh it after being taken out and after 2 consecutive measurements with the balance one can stop drying it. This once again, touches upon the issue of achieving high