When standard solution of NaOH is left in air for few hours
Question
When standard solution of NaOH is left in air for few hours
Solution
When a standard solution of NaOH is left in the air for a few hours, several steps can be observed:
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Initially, the NaOH solution is in a stable state, with a known concentration and pH level.
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As the solution is exposed to the air, it starts to react with carbon dioxide (CO2) present in the atmosphere. This reaction leads to the formation of sodium carbonate (Na2CO3) and water (H2O).
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The presence of sodium carbonate in the solution causes a decrease in the concentration of NaOH. This is because some of the NaOH molecules are converted into Na2CO3.
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The pH of the solution also changes due to the formation of sodium carbonate. Sodium carbonate is a weak base, so it increases the pH of the solution.
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Over time, if the NaOH solution is continuously exposed to the air, the concentration of NaOH will continue to decrease, and the pH will continue to rise.
It is important to note that the rate at which these changes occur depends on various factors, such as the concentration of NaOH, the temperature, and the amount of carbon dioxide in the air. Therefore, it is recommended to store NaOH solutions in airtight containers to minimize these changes and maintain their stability.
Similar Questions
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