Ionic Equilibrium In Solution

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Among the given, only potassium chloride is a strong electrolyte, so its degree of dissociation is almost unity

Concept: Chemistry (Equilibrium) - pH Calculation of Strong Acids.

Step 1: Understand the nature of the given acid. A strong dibasic acid (like in its primary dissociation) is assumed to completely dissociate into its ions in an aqueous solution, yielding two moles of hydrogen ions ( or ) per mole of the acid.

Step 2: Determine the concentration of hydrogen ions. The molarity of the acid ( ) is given as . Since the acid is dibasic and fully dissociates, the concentration of hydrogen ions will be twice the concentration of the acid. .

Step 3: Set up the pH formula. The formula for pH is . Substitute the calculated hydrogen ion concentration: .

Step 4: Expand the logarithmic expression. Using the property of logarithms ( ): . Since , this becomes: .

Step 5: Evaluate the final numerical value. The standard logarithmic value for is approximately . Substitute this value into the equation: . Rounding to one decimal place to match the given options yields . $ $

Concept: Chemistry - Acids and Bases (Lewis Theory).

Step 1: Recall the Lewis theory of acids and bases. According to the theory proposed by G.N. Lewis, acid-base reactions are defined entirely by the transfer of electron pairs, without any requirement for hydrogen or hydroxide ions.

Step 2: Define a Lewis acid. A Lewis acid is defined as any chemical species that is electron-deficient and capable of accepting a pair of electrons to form a coordinate covalent bond.

Step 3: Define a Lewis base. Conversely, a Lewis base is defined as any chemical species that has at least one lone pair of electrons and is capable of donating this electron pair to a Lewis acid.

Step 4: Evaluate the given options against the definitions. Option (A) defines a Lewis acid. Option (C) defines a Brønsted-Lowry base (proton acceptor). Option (D) defines an Arrhenius base (hydroxide donor).

Step 5: Conclude the correct characteristic. Only Option (B), "donate a pair of electron", correctly matches the fundamental definition of a Lewis base. $ $

Step 1: Given concentration M and degree of dissociation $ $

Step 1: Understand ionic compounds.
Ionic compounds are formed by the transfer of electrons between a metal and a non-metal, resulting in the formation of ions.
Step 2: Analyze the given options.
, , and are covalent compounds formed between non-metals.
Potassium iodide consists of potassium (a metal) and iodine (a non-metal), forming an ionic bond.
Step 3: Conclusion.
Hence, potassium iodide is an ionic compound.

The dissociation of in water is: Given the pH is 9, the is: The concentration of is: From the stoichiometry of the reaction: The solubility product ( ) is: ---
Final Answer:

The pH of a solution is calculated using the formula: Given: So, the solution has a pH of 4, indicating it's acidic.

The pH of an aqueous salt solution can be determined by considering the acid dissociation constant (Ka) and base dissociation constant (Kb). We can use the following relation: Given: - pKa of HA = 4 - pKb of BOH = 5 Thus, Thus, the pH of the solution is 7.5.

Concept: is a strong base and completely dissociates in water: Thus the hydroxide ion concentration equals the molarity of . Also, and
Step 1: {Calculate .}
Step 2: {Find the pH.}

Concept: For a strong base like : and at .

Step 1: Determine the hydroxide ion concentration. Since is a strong base, it completely dissociates:

Step 2: Calculate pOH.

Step 3: Find pH.

Concept: A weak base partially dissociates in water. If the base is represented as , the dissociation equilibrium can be written as: The equilibrium constant for a weak base is called the base dissociation constant . If the initial concentration of the base is and the degree of dissociation is :
• Concentration of dissociated base =
• Concentration of formed =
• Concentration of formed =
• Remaining base concentration = Since weak bases dissociate very slightly, we approximate: This simplifies the calculation of .

Step 1: Write the equilibrium expression for .

Step 2: Substitute the concentrations using degree of dissociation.

Step 3: Apply the approximation for weak bases. Since is very small: Thus,

Step 4: Identify the correct option. Therefore, the correct relation between and is:

Concept:
The pH of a solution is defined as the negative logarithm of the hydrogen ion concentration in the solution. :contentReference[oaicite:0]{index=0} Nitric acid ( ) is a strong acid and completely dissociates in water, producing hydrogen ions.

Step 1: Write the concentration of hydrogen ions. Since is a strong acid,

Step 2: Substitute into the pH formula.

Step 3: Calculate the value. Hence,