Acids, Bases Buffers Essays

Acids, Bases Buffers Essays Acids, Bases Buffers Paper Acids, Bases Buffers Paper To measure the buffering capacity of two types of Isotonic drinks. Introduction: There are acid-forming. Basic forming and neutral food, however the acid or alkaline properties of a food is unable to judge by the actual acidity of the food itself. For example, citrus fruits such as lemon are acidic, but they are alkaline-forming when we consume and digest it. Therefore the food acidity or alkalinity only can determined when it is break down and digested. To maintain a healthy diet, acid- ease balance diet is very important. An acid-base buffer is a solution that lessens the impact on pH from addition of acid and base. The essential feature of a buffer means that it consists of high concentrations of the acidic (HA) and basic (A-) components. When small amount of HUH+ or OH- Ions are added to the buffer, they cause a small amount of one buffer component to convert Into the other, which change the relative concentration of the two component. For any weak acid, HA, the dissociation equation and Aka expression are: The final expression of pH obtained after logarithms applied to both side. Buffer capacity is a measure of the ability to resist pH change and depends on both the absolute and relative component concentration. The buffer capacity is affected by the relative concentration of the buffer component which the buffer capacity in increasing with the concentration of the components of a buffer. For a given addition of acid or base, the buffer component concentration ratio change less when the concentration are similar than what they are different. Materials: Acetic acid (MM=60 g/mol), Noah solution (0. MM), HCI solution (0. 001 M), calibration buffer (pH. 5 and pH 5. 5), 7-UP, 100 Plus. Based on El Chatterer principle, the equilibrium of the system will shifts to the left to suppress the acid from dissociating as much as it would in water and causes the [HUH+] decreased. Therefore higher pH (less acidic) obtained with increasing of the sodium acetate added. This is because the common ion effect that acetate ion CHOC- play the role as common ion for both the acetate acid and the sodium acetate solution. Buffer by 1 unit for acetate solution is the highest and for the 0. MOM HCI is the lowest. Same case goes with their buffer capacity that have been calculated. This implies that the more concentrated the buffer, the greater its capacity, and the larger the resist of pH change. For the 7-JP and citrate buffer is present in the solution which in the form of sodium citrate. The percentage error obtained in this experiment is considerable high for both buffer and HCI acid solution. There are several factors that may be possible lead to the occurrence of error: The solution is not homogeneous because not stirred well before adding sodium acetate Systematic error maybe happened especially acetic acid measurement taking for 2 decimal places by using a ml pipette. For the titration between HCI and Noah solution is strong acid and strong base titration. They will both fully dissociate, which mean all the molecules of acid and base will completely separate into ions. Therefore, the Noah solution needed to change the pH of HCI solution is lesser than the titration of acetate buffer with Noah solution. HCI + Noah attach + H2O Recommendations: The error of the experiment can be reduced by using microcomputer for the 2 decimal place volume of acetic acid that need to take, instead of pipette which has ml. Besides, the glass rod may hit the pH meter bulb and it is unable to let the solution keep stirring, therefore the magnetic stirrer bar is recommended here to be used in order to have constant stirring to ensure the solution is homogeneous. Question and Answer: 1. Based on the results in the experiment, which beverage (7-up or 100-Plus) shows a better buffer capacity? Why? Answer: In this experiment, 100-Plus has better buffering capacity than the 7-JP. Buffer capacity is the measure of this buffer ability to resist pH change and depends on both the absolute and relative component concentrations. The greater the buffer capacity of the buffer system, the more acid or base is required to change the pH of the buffer system. In this experiment, the average volume of Noah solution used to increase 1 unit of pH is higher in 100-plus. 2. What are the chemical components in 7-JP and which are involved in determining the buffer capacity of these soft drinks? Answer: The chemical components involved in determining the buffer capacity of 7-up and 100-plus are iatric acid, its conjugate base, citrate, carbon dioxide and its conjugate base carbonic acid.