Which solution(s) showed the greatest change in pH? Why? Which solutions(s) showed little or no change in pH? Why? 06 Normally, the pH of the human body is fixed in a very narrow range between 7.35 and 7.45. A patient with an acidotic blood pH of 7.3 may be treated with an alkali such as sodium hydrogen carbonate. Why would this treatment raise the pH of the blood? Name Date Section Instructor Team Pre-Lab Study Questions I. What happens when a fatty acid is reacted with NaOH? 2. Why is ethanol added to the reaction mixture of fat and base in the making of soap?
The Correct Answer and Explanation is :
1. Reaction of Fatty Acids with NaOH:
When a fatty acid reacts with sodium hydroxide (NaOH), a neutralization reaction occurs, resulting in the formation of a carboxylate salt and water. This process is known as saponification. For example, when oleic acid (a common fatty acid) reacts with NaOH, it produces sodium oleate (a soap) and water. The reaction can be represented as:
[ \text{Fatty Acid} + \text{NaOH} \rightarrow \text{Carboxylate Salt (Soap)} + \text{Water} ]
This reaction is fundamental in soap-making processes.
2. Addition of Ethanol in Soap Making:
Ethanol is often added to the reaction mixture of fat and base during soap making to act as a solvent. It helps in dissolving the fat and NaOH, facilitating the saponification process. Additionally, ethanol can assist in the separation of glycerol from the soap, improving the purity of the final product.
3. Treatment of Acidotic Blood with Sodium Bicarbonate:
The human body maintains a narrow pH range between 7.35 and 7.45. When blood pH drops below this range, a condition known as acidosis occurs. To correct this, sodium bicarbonate (NaHCO₃) is administered. Sodium bicarbonate acts as a buffer, neutralizing excess hydrogen ions (H⁺) in the blood. The reaction can be represented as:
[ \text{NaHCO₃} + \text{H⁺} \rightarrow \text{H₂CO₃} \rightarrow \text{CO₂} + \text{H₂O} ]
This reaction reduces the concentration of free hydrogen ions, thereby increasing the blood pH back to normal levels.