Table of contents

1. Matter and Measurements4h 31m
2. Atoms and the Periodic Table5h 23m
3. Ionic Compounds2h 18m
4. Molecular Compounds2h 18m
5. Classification & Balancing of Chemical Reactions3h 17m
6. Chemical Reactions & Quantities2h 27m
7. Energy, Rate and Equilibrium3h 46m
8. Gases, Liquids and Solids3h 25m
9. Solutions4h 10m
10. Acids and Bases3h 29m
11. Nuclear Chemistry56m
BONUS: Lab Techniques and Procedures1h 38m
BONUS: Mathematical Operations and Functions47m
12. Introduction to Organic Chemistry1h 34m
13. Alkenes, Alkynes, and Aromatic Compounds2h 12m
14. Compounds with Oxygen or Sulfur1h 6m
15. Aldehydes and Ketones1h 1m
16. Carboxylic Acids and Their Derivatives1h 11m
17. Amines39m
18. Amino Acids and Proteins1h 51m
19. Enzymes1h 37m
20. Carbohydrates1h 41m
21. The Generation of Biochemical Energy2h 8m
22. Carbohydrate Metabolism2h 22m
23. Lipids2h 26m
24. Lipid Metabolism1h 45m
25. Protein and Amino Acid Metabolism1h 37m
26. Nucleic Acids and Protein Synthesis2h 54m

10. Acids and Bases

Gas Evolution Equations (Simplified)

GOB Chemistry

10. Acids and Bases

Gas Evolution Equations (Simplified)

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2:19 minutes

Problem 109b

Textbook Question

Obtain a package of Alka-Seltzer, an antacid, from the local drug store:
b. Why does Alka-Seltzer foam and bubble when dissolved in water? Which ingredient is the antacid?

Verified step by step guidance

Step 1: Understand the chemical reaction that occurs when Alka-Seltzer is dissolved in water. Alka-Seltzer contains sodium bicarbonate (NaHCO₃) and citric acid (C₆H₈O₇). When these ingredients come into contact with water, they react to produce carbon dioxide gas (CO₂), which causes the foaming and bubbling.

Step 2: Write the chemical equation for the reaction. The reaction between sodium bicarbonate and citric acid can be represented as:

{NaHCO}_{3} + C_{6} H_{8} O_{7} \to {Na}_{3} C_{6} H_{5} O_{7} + {CO}_{2} + H_{2} O

Step 3: Identify the antacid ingredient in Alka-Seltzer. Sodium bicarbonate (NaHCO₃) is the antacid component. It works by neutralizing stomach acid (hydrochloric acid, HCl) to relieve symptoms of indigestion and heartburn.

Step 4: Explain the neutralization reaction of sodium bicarbonate with stomach acid. The reaction can be represented as:

{NaHCO}_{3} + HCl \to NaCl + {CO}_{2} + H_{2} O

Step 5: Summarize the process. The foaming and bubbling occur due to the production of carbon dioxide gas during the reaction between sodium bicarbonate and citric acid. Sodium bicarbonate is the antacid ingredient that neutralizes stomach acid, providing relief from indigestion.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Chemical Reaction

The foaming and bubbling of Alka-Seltzer when dissolved in water is a result of a chemical reaction between its ingredients, primarily sodium bicarbonate and citric acid. When these two compounds come into contact with water, they react to produce carbon dioxide gas, which forms bubbles and creates the characteristic fizzing effect.

Antacid Function

Alka-Seltzer contains sodium bicarbonate, which acts as the active antacid ingredient. Antacids neutralize stomach acid, providing relief from heartburn and indigestion by increasing the pH level in the stomach, thus alleviating discomfort caused by excess acidity.

Dissolution Process

The dissolution process refers to how solid substances, like the tablets in Alka-Seltzer, break down in a solvent, such as water. This process is essential for the chemical reaction to occur, as it allows the reactants (sodium bicarbonate and citric acid) to interact and produce the gas that causes the foaming effect.

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