Alka-Seltzer Background Product information: Alka-Seltzer is an effervescent antacid used for the relief of headache, heartburn, and hangovers while neutralizing excess stomach acid. Alka-Seltzer is a combination of aspirin (acetylsalicylic acid), sodium bicarbonate (NaHCO3)- which is baking soda, and citric acid. This solution is designed to treat pain as well as neutralize excess stomach acid. It is made on the form of large effervescent tablets which are dissolved in water. As the tablets dissolve, the base (bicarbonate) and the acid (citric acid) react with each other producing carbon dioxide gas (which is where the “Seltzer” comes from). This produces enough agitation or action in the solution to allow the active ingredients (aspirin) to dissolve slowly. Then solution is then ingested for digestion relief. Chemistry of the effervescence: Though important to the overall effect of the medication, the aspirin (acetylsalicylic acid) does not contribute to the effervescent action of Alka-Seltzer; the effervescence is produced by the baking soda (sodium bicarbonate) and the citric acid reacting to form sodium citrate and carbon dioxide gas. The chemical reaction for this is as follows. C6H8O7 + 3NaHCO3 → 3H2O + 3CO2 + Na3C6H5 O7
citric acid + baking soda → water + carbon dioxide + socium citrate Uses of Alka-Seltzer: It is used as an antacid to treat indigestion Drop 2 tablets in the toilet and wait 20 minutes, brush and flush. The effervescence action cleans the toilet Cleans vases, polishes jewelry and removes the burned-on grease from a pot or pan Unclogs drains Soothes insect bites Factors that affect the rates of chemical reactions: It is helpful to predict whether an action will affect the rate at which a chemical reaction proceeds. There are several factors that can influence the rate of a chemical reaction. Concentration of reactants: Concentration means a higher amount of the reactants, or more simply put-more of the stuff that is causing the chemical reaction! If there are more reactant, there are more particles to collide, or bump into each other, which will make the reaction go faster. Temperature: Usually, an increase in temperature is accompanied by an increase in the reaction rate. An increase in temperature causes the molecules to move faster, which will cause the reaction to happen faster. Environment reaction takes place in: The kind of solution the reaction takes place in can affect the rate of reaction. Many reactions happen faster in a liquid, rather than in a solid or a gas. Presence of a catalyst: A catalyst is something that is added to a reaction that can either speed up or slow down a reaction, but is not part of the reaction. It is like coating a baking pan with oil before baking a cake. It is not one of the ingredients needed to bake a cake, but it sure makes it easier to get it out of the pan, and helps the cake bake without burning the bottom. Sometimes chemicals, or catalysts are added to speed up or slow down a reaction so that the resulting products are made more efficiently. Like a better cake!
Name___________________________________Period________Date_________ MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Stress-inoculation therapy is one type of ________ therapy. 2) Showing a client how his or her irrational and self-defeating beliefs are causing problems is MOST characteristic of ________ ther
Summary of the annual meeting of the SEWG Transient Heat Loads on 1/2 September 2010 in Jülich This SEWG addresses the heat loads arising during transient events like ELMs and disruptions and the development of techniques to mitigate these heat loads. In 2010, the scope of this group was extended to also include the assessment of inter-ELM heat flux with respect to far-SOL transport,