Calcule el pH de las siguientes disoluciones de ácidos fuertes: (a) HNO3 0.0575 M; (b) 0.723 g

Calcule el pH de las siguientes disoluciones de ácidos...

Calcule el pH de las siguientes disoluciones de ácidos fuertes: (a) $\mathrm{HNO}_3 0.0575 \mathrm{M}$; (b) $0.723 \mathrm{~g}$ de $\mathrm{HClO}_4$ en $2.00 \mathrm{~L}$ de disolución; (c) $5.00 \mathrm{~mL}$ de $\mathrm{HCl} 1.00 \mathrm{M}$ diluidos a $0.750 \mathrm{~L}$; (d) una mezcla constituida por $50.0 \mathrm{~mL}$ de $\mathrm{HCl}$ $0.020 \mathrm{M}$ y $125 \mathrm{~mL}$ de $\mathrm{HI} 0.010 \mathrm{M}$.

Key Concepts

Stoichiometry in Acid-Base Calculations

Stoichiometry provides the quantitative relationships between reactants and products in chemical reactions. When mixing solutions or calculating the number of moles present from a given mass, stoichiometric principles allow for the determination of the total hydrogen ion concentration, which is essential for accurate pH calculations.

Dilution of Solutions

Dilution involves reducing the concentration of a solution by adding more solvent. The resulting concentration can be calculated using the relationship that the product of the initial concentration and volume equals the product of the final concentration and volume. This concept is critical when preparing solutions or mixing different volumes of acids.

Molarity and Concentration

Molarity, defined as moles of solute per liter of solution, is fundamental to quantitative chemical problems. In the context of acid solutions, knowing the molarity allows for direct calculation of the hydrogen ion concentration when the acid fully dissociates.

pH Calculation

The pH scale measures the acidity or basicity of a solution and is defined mathematically as pH = -log[H+], where [H+] is the molar concentration of hydrogen ions in the solution. This logarithmic relationship means that a small change in [H+] can result in a significant change in pH, making it a key concept in understanding acid-base chemistry.

Strong Acid Dissociation

Strong acids are characterized by their complete dissociation in aqueous solutions. This means that the concentration of hydrogen ions produced is equal to the initial concentration of the acid, simplifying pH calculations because no equilibrium needs to be considered.