Vinegar reaction with baking soda

The Chemical Puzzler involves the reaction with baking soda and acetic acid. Explain why the evolution of CO2 gas eventually ceases as more and more vinegar is added to a NaHCOs sample. Suppose you began with 5.0 g of NaHCOj. What quantity of acetic acid would you have to add to just get to the point where CO2 evolution ceases ... 

You have probably already encountered the reaction of vinegar with baking soda. The carbon dioxide that is produced can be used to simulate a volcano, for example, or to propel a toy car or rocket. 

Baking soda is a chemical called sodium bicarbonate. Vinegar is water that contains a small amount of a chemical called acetic acid. When vinegar is mixed with baking soda, a chemical reaction occurs. 

Weak acids and bases will also undergo neutralization reactions. The reaction of the acetic acid (HAc) in vinegar with the sodium bicarbonate (NaHCOs) in baking soda produces water, sodium ions (Na+), acetate ions (Ac), and carbon dioxide gas (CO2). The reaction between baking soda and acids in dough creates bubbles of carbon dioxide that make cakes and cookies rise and become fluffy. 

Look closely at the equation that represents the reaction of baking soda with vinegar. 

We know from the conservation of mass that when we run a reaction in a batch reactor the mass of products must be equal to the mass of reactants so long as nothing has escaped from the reactor. This holds absolutely and is independent of the chemical reaction type, mechanism, or stoichiometry. All that chemical reactions do is to rearrange the atoms and mass in the molecules. In essence the labels on the mass change but that is all. If the reaction in solution leads to a gas such as the reaction of baking soda with vinegar water (that is, sodium bicarbonate with dilute acetic acid), then a mass change can take place because one of the products is a gas and can escape the vessel ... 

In some ways, chemistry is similar to baking. To carry out a reaction successfully—in chemistry or in baking—you need to know how much of each reactant you will need. When you bake something with vinegar and baking soda, for example, the baking soda reacts with acetic acid in the vinegar to produce carbon dioxide gas. The carbon dioxide gas helps the batter rise. The chemical equation for this reaction is... 

Describing What Happens Bubbles tell you that a gas has been produced, but they don t tell you what kind of gas. Are bubbles of gas the only product, or do some atoms from the vinegar and baking soda form something else What goes on in the chemical reaction can be more than what you see with your eyes. Chemists try to find out which reactants are used and which products are formed in a chemical reaction. Then, they can write it in a shorthand form called a chemical equation. A chemical equation tells chemists at a glance the reactants, products, physical state, and the proportions of each substance present. This is very important as you will see later. 

Add 1 teaspoon of hot water, and % of a teaspoon of baking soda to the cup containing the chopped-up curd. The mixture may foam a little from the reaction of the baking soda with the remaining vinegar, producing carbon dioxide gas. 

I work with a lot of elementary school children, and they love science. I show them chemical reactions (vinegar plus baking soda, for example), and they go wild. And that s what I hope happens to you. 

Did you ever make a day volcano in kindergarten that erupted when filled with vinegar, baking soda, and red food coloring for effect Have you pushed the gas pedal of a car and felt the acceleration as the car moved forward Have you wondered why laxmdry detergents work better than normal soap to clean your clothes Each of these processes involves a chemical reaction—the transformation of one or more substances into different substances. 

In the classic kindergarten volcano, the baking soda (which is sodium bicarbonate) reacts with acetic acid in the vinegar to form carbon dioxide gas, water, and sodium acetate. The newly formed carbon dioxide bubbles out of the mixture, causing the eruption. Reactions that occur in liquids and form a gas are gas evolution reactions. A similar reaction causes the fizzing of antacids such as Alka-Seltzer . ... 

Here, a carbonate (sodium carbonate) reacts with an acid (hydrochloric acid) to produce a salt (sodium chloride), water, and carbon dioxide gas. A similar reaction is shown in Figure 4.10, in which baking soda (sodium hydrogen carbonate) reacts with the acetic acid in vinegar. Note the bubbles of carbon dioxide gas that evolve during the reaction. This reaction of a carbonate with an acid is the basis of a simple test for carbonate minerals. When you treat a carbonate mineral or rock, such as limestone, with hydrochloric acid, the material fizzes, as bubbles of odorless carbon dioxide form. 

Production of a gas. The evolution of gas bubbles when two substances are mixed is often evidence of a chemical reaction. For example, bubbles of carbon dioxide gas form immediately when baking soda is mixed with vinegar, as shown in Figure 1.2a. 

The most widely practiced reactions convert carboxylic acids into esters, amides, carboxylate salts, acid chlorides, and alcohols. Carboxylic acids react with bases to form carboxylate salts, in which the hydrogen of the hydroxyl (-OH) group is replaced with a metal cation. Thus, acetic acid found in vinegar reacts with sodium bicarbonate (baking soda) to form sodium acetate, carbon dioxide, and water ... 

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