Sodium bicarbonate, with the chemical formula NaHCO3, is the white powder widely known as baking soda. A similar compound is sodium carbonate (Na2CO3), used as a cleaning agent or an additive during clothes washing. The basic test for the presence of carbonate salts is a reaction with a diluted acid solution that leads to release of bubbles of the gas carbon dioxide and follows the reaction: NaHCO3 + HCl = NaCl + H2O + CO2. An additional test is required to distinguish between sodium bicarbonate and sodium carbonate. Weigh approximately 2 g of the sample and put the substance in the beaker. Pour approximately 10 ml of the distilled water into the beaker. Mix the solution with the spoon until the salt dissolves completely. Pour the half of the solution into the second beaker. Using a plastic pipette, add about 2 ml of the hydrochloric acid solution into the first beaker. If bubbles of the gas (carbon dioxide) intensely evolve during the reaction, then the sample is a carbonate salt (NaHCO3 or Na2CO3); proceed to the next step. Cut a piece of the hydrion pH paper about 1.5 inches long. Holding one end of the paper strip, dip the other end into the solution in the second beaker for 1 to 2 seconds, and then take it out. The part of the paper that has been in the solution will change color. Compare the color of the pH paper with the pH scale typically printed on the pH paper pack and assign pH of the solution accordingly. If pH is around 8, the sample is sodium bicarbonate. If pH is in the range 9.5 to 10, it is sodium carbonate Carbonate— Carbonates and bicarbonates effervesce with acids, evolving a colorless gas that, when passed into calcium hydroxide TS, produces a white precipitate immediately. A cold solution (1 in 20) of a soluble carbonate is colored red by phenolphthalein TS, while a similar solution of a bicarbonate remains unchanged or is only slightly colored.
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Baking soda, also known as sodium bicarbonate, is widely used in baking.
This is because it has leavening properties, meaning it causes dough to rise by producing carbon dioxide. Aside from cooking, baking soda has a variety of additional household uses and health benefits. Here are 23 benefits and uses of baking soda. In 1863, Ernest Solvay discovered a new process for manufacturing sodium carbonate using sea salt, ammonia and carbonic acid. This process produced a sodium bicarbonate of high purity, which is used today in many fields: food, detergents, health and remediation. Over time, the group has grown and now Solvay, with a presence in 55 countries on five continents, is the world leader in sodium carbonate and bicarbonate with manufacturing plants in the United States and Europe. The use of baking soda as a fungicide is not a new idea. In Alfred C. Hottes’ A Little Book of Climbing Plants, published in 1933 by the A.T. De La Mare Co. of New York, mention is made of using one ounce of baking soda per gallon of water to control powdery mildew (PM) on climbing roses. The author credits the idea to a Russian plant pathologist, A. de Yaczenski In the August, 1985 issue of Organic Gardening magazine, a short article by Warren Shultz entitled “Recipe for Resistance” reports that researchers in Japan obtained effective control of PM on cucumbers, eggplants, and strawberries. They suggested weekly sprays of ¼ ounce baking soda per gallon of water. Baking soda is a common name for sodium hydrogen carbonate or NaHCO 3(s) . It is a
useful compound that can be found in many everyday products. The Athenium Baking Soda Company recently started producing sodium bicarbonate using a method that reacts crystalline ammonium hydrogen carbonate with brine, which contains high concentrations of sodium chloride as well as traces of potassium chloride, lithium chloride, and calcium chloride that may be present in the dry residue. Because of this, the Athenium Baking Soda Company wants to hire quality control scientists to test for contaminants in their baking soda. To do this, the Athenium Baking Soda Company has decided that applicants compete to analyze the composition and purity of baking soda samples. The purpose of this experiment is to analyze the composition of the baking soda using two different methods to figure out the percentage of NaHCO 3 in the baking soda manufacturers and by determining the impurities present in the sample. This experiment will enable our team to use what we learned in the Thermal Gravimetric Analysis Lab (Experiment 4), Emission Analysis of Aqueous Solutions of Groups IA and IIA Metal Salts Lab (Experiment 10), and Determination of the Concentration of Acetic Acid in Vinegar Lab (Experiment 12). The methods learned in these previous experiments will be used except with different reagents. By combining the methods learned into one experiment, the experiment reinforces knowledge as well as provides a better understanding of chemistry as a science. The baking soda price will be analyzed for metal ion contaminants with a MeasureNet spectrophotometer using emission spectroscopy. Spectroscopy is best explained as a measure of molecular energy levels which are most commonly expressed in the form of emissions or absorptions. |