3. How does dissolved CO2 in distilled water affect the accuracy of the determination of a NaOH solution's concentration?
The CO2 in the distilled water will create a more acidic solution which will affct the determination of NaOH solution's concentration? How is the term acid anhydride applied to this problem?
Would it decrease it the concentration of NaOH solution's concentration?
I answered the first part for you but you may not have liked it. Most (and some prof too I think) believe dissolved CO2 affect the value for M NaOH no matter what.
The anhydride (anhydride means without water) of an acid is a material which produces that acid when added to water.
CO2 + H2O ==> H2CO3.
SO3 + H2O ==> H2SO4
N2O5 + H2O ==> 2HNO3
P2O5 + 3H2O ==> 2H3PO4 (or if you prefer P4O10 + 6H2O ==> 4H3PO4)
CO2 is the anhydride of H2CO3
SO3 is the anhydride of H2SO4
etc.
The presence of dissolved CO2 in distilled water affects the accuracy of determining the concentration of a NaOH solution in the following ways:
1. Lower pH: Dissolved CO2 reacts with water to form carbonic acid, which increases the acidity of the solution. This lower pH can interfere with the determination of NaOH concentration because the reaction between NaOH and acid will produce a neutralization reaction that consumes both the acid and the base.
2. Consumption of NaOH: The carbonic acid formed from dissolved CO2 can react with NaOH, leading to the neutralization of NaOH and the formation of sodium bicarbonate (NaHCO3). This means that some NaOH will be consumed by the acid-base reaction with carbonic acid instead of being available for the determination of its concentration.
The term "acid anhydride" refers to a substance that can react with water to form an acid. In this case, CO2 can be considered an acid anhydride as it reacts with water to form carbonic acid. The presence of CO2 in distilled water creates carbonic acid, which contributes to the increased acidity of the solution.
Overall, the presence of dissolved CO2 in distilled water will decrease the accuracy of the determination of NaOH solution's concentration by introducing additional acid-base reactions and consuming some of the NaOH.
The presence of dissolved CO2 in distilled water can indeed affect the accuracy of determining the concentration of a NaOH solution. When CO2 dissolves in water, it forms carbonic acid (H2CO3), which increases the acidity of the solution. This increase in acidity can react with NaOH during titration, leading to a decrease in the measured concentration of NaOH.
The term "acid anhydride" is not directly applied to this problem. An acid anhydride is a compound formed by removing water from two acid molecules. However, carbon dioxide is not an acid anhydride but rather a weak acid itself (carbonic acid).
The decrease in the concentration of NaOH solution during titration is due to the reaction between NaOH and carbonic acid. This reaction consumes some of the NaOH, resulting in a lower concentration being measured. To mitigate this effect, the dissolved CO2 can be removed from the distilled water before using it in the determination of NaOH concentration.