Given below are two statements :

Statement (I) : A Buffer solution is the mixture of a salt and an acid or a base mixed in any particular quantities

Statement (II) : Blood is naturally occurring buffer solution whose $\mathrm{pH}$ is maintained by $\mathrm{H}_2 \mathrm{CO}_3 / \mathrm{HCO}_3{ }^{\ominus}$ concentrations.

In the light of the above statements, choose the correct answer from the options given below :

<p>Let's analyze both statements given to determine the correct answer.</p> <p>Statement (I) describes a buffer solution as a mixture of a salt and an acid or a base mixed in any particular quantities. However, this definition is partially incorrect. A buffer solution is more accurately defined as a mixture of a weak acid and its conjugate base or a weak base and its conjugate acid. The purpose of a buffer solution is to maintain a stable pH when small amounts of acid (H⁺ ions) or alkali (OH⁻ ions) are added. It is not just any mixture of a salt and an acid or base but must involve components that can react with added acid or base to minimize changes in pH.</p> <p>Therefore, Statement (I) is misleading or incomplete as it omits the necessity for a weak acid and its conjugate base or a weak base and its conjugate acid to form a true buffer solution.</p> <p>Statement (II) mentions that blood is a naturally occurring buffer solution whose pH is maintained by the $\mathrm{H}_2\mathrm{CO}_3/\mathrm{HCO}_3^{-}$ (carbonic acid/bicarbonate) system. This is accurate. The carbonic acid-bicarbonate buffering system is one of the main buffering systems in human blood, helping to maintain the pH within a narrow range (typically around 7.35 to 7.45). This buffer system works by the reversible reaction between carbon dioxide (CO₂) and water to form carbonic acid ($\mathrm{H}_2\mathrm{CO}_3$), which can then dissociate into bicarbonate ion ($\mathrm{HCO}_3^{-}$) and a hydrogen ion (H⁺). This system effectively moderates changes in pH by either consuming or releasing H⁺ ions.</p> <p>Given this analysis:</p> <p>Statement I is false because it inaccurately or incompletely describes a buffer solution.</p> <p>Statement II is true as it correctly identifies blood as a naturally occurring buffer solution that uses the $\mathrm{H}_2\mathrm{CO}_3/\mathrm{HCO}_3^{-}$ system to maintain pH.</p> <p>Therefore, the correct answer is:</p> <p>Option C: Statement I is false but Statement II is true.</p>