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Right answer is (c) 10^-5

Explanation: For the salt AXBY, (AxBy = xA^y+ + yB^x+), the solubility of a sparingly soluble salt is given by x^x.y^y.s^x+y. Ksp = x^x.y^y.s^x+y, where x = 2 and y = 3; Ksp = 108S5 = 1 x 10^-25. S = 10^-5. The solubility of the salt is given by 10^-5.

Correct option is (b) false

The explanation is: SOLUBILITY of the product is only APPLICABLE to the saturated solutions, WHEREAS an ionic product is applicable to all TYPES of solutions. It is because the formation of a precipitate is dependent on the solubility product.

Correct option is (d) (Ksp/27)^1/4

To elaborate: For the salt AxBy, (AxBy = xA^y+ + yB^x+), the SOLUBILITY of a sparingly SOLUBLE salt is given by x^x.y^y.s^x+y. Ksp = x^x.y^y.s^x+y, where x = 1 and y = 3; Ksp = 27S^4, by rearranging, we get solubility denoted by S as (Ksp/27)^1/4.

Correct option is (a) true

The explanation: Yes, we can predict the SOLUBILITY of a sparingly soluble SALT, for EXAMPLE, consider the reaction; AxBy = xA^y+ + yB^x+, the solubility of a sparingly soluble salt is given by x^x.y^y.s^x+y, knowing the values of KSP, x and y, the solubility of the salt can be calculated.

Correct OPTION is (a) GREATER than the SOLUBILITY product

For explanation I would say: The concept of solubility product helps in predicting the formation of the precipitate. In general, if the ionic product is greater than the solubility product, the precipitate is FORMED and if the ionic product is less than the solubility product, the precipitate is not formed.

The correct option is (b) boric acid / borax is an acidic buffer

For explanation: Ammonium hydroxide / ammonium CHLORIDE is a BASIC buffer, henderson hasselbalch equation is GIVEN by PH = pKa + log[salt]/[acid] and pH + pOH = 14. So the only correct statement is that boric acid / borax is an acidic buffer.

The correct option is (b) 4.85

The best EXPLANATION: ACCORDING to the Henderson hasselbalch EQUATION pH = pKa + log[salt]/[acid], if we substitute the concentration of salt as 1 M and the concentration of acid as 0.8 M, pH = 4.752 + 0.097 = 4.849 is the REQUIRED answer.

Right choice is (d) 11

The best I can EXPLAIN: We KNOW that the sum of the PH and pOH of any substance is EQUAL to 14 that is pH + pOH = 14. So here the pH of a substance is given by 3 the pH of the substance = 14 – 3 = 11, 11 is the required answer.

The correct answer is (B) 5.14

Explanation: We have henderson-hasselbalch equation as PH = PKA + LOG[salt]/[ACID]. So by substituting the concentrations of silent and acid along with the acid dissociation constant, we get pH = -log[1.8 × 10^-5] + log [0.50mol/L]/[0.20mol/L] = 5.14.

Right choice is (a) 2

The explanation: Buffer capacity is denoted by Φ = NUMBER of MOLES of acid or base ADDED to one litre of the buffer by a change in PH. Here the change in pH is given by 1 and the buffer capacity is given by 2, therefore by substituting, we get that 2 moles of acid or base are added in one litre of the solution.

Correct option is (d) 0.3

For explanation: Buffer CAPACITY is defined as the number of moles of acid or BASE added in ONE litre of the solution to change the pH by Unity. Therefore here buffer capacity = 3/5 DIVIDED by 2 = 0.6/2 = 0.3. The buffer capacity is given as 0.3.

Correct answer is (a) ADDITION of WEAK base

The best explanation: If the addition of a strong acid or base changes the pH of a buffer by unit, the buffer solution is assumed to be DESTROYED that is new pH = pKa ± 1; that MEANS [salt]/[acid] or [acid]/[salt] = 10 or 1/10.

The correct CHOICE is (C) Ammonium hydroxide-ammonium chloride

To EXPLAIN: An ACIDIC buffer has a pH VALUE of less than 7, Acetic Acid-Sodium Acetate and boric acid-borax are examples of acidic buffers, but ammonium Hydroxide-ammonium chloride has a pH of greater than 7, so they are basic buffers.

The CORRECT choice is (a) true

The explanation: A solution that resists the change in its PH value by the ADDITION of a small amount of acid or base is CALLED a BUFFER solution. The buffer system present in the blood is carbonic acid and sodium bicarbonate.

Correct answer is (a) HF ≪ HCl ≪ HBr ≪ HI

The BEST explanation: The correct order of INCREASE in ACIDIC STRENGTH is HF ≪ HCl ≪ HBr ≪ HI. There are many FACTORS affecting acid strength. Hear the hydrogen-acid Bond strength decreases, as the acid strength increases.

The CORRECT answer is (b) 4.2

Easy EXPLANATION: The dissociation constant K = [H^+][HCOO^–]/[HCOOH] = x^2/0.1 – x = 1.77 x10^-4; x = [H^+] = 0.0042M. The percent of dissociation is x/0.1 = (0.042M)100% = 4.2. THEREFORE the value of DEGREE of dissociation is 4.2

The correct OPTION is (B) 2

Best explanation: pH is defined as the negative logarithm of hydrogen ion concentration that is pH = -log[H^+]. So here, the pH of the solution of sulphuric acid is -log[H^+], where concentration of hydrogen ion is 0.01M = -log[10^-2] = 2.

The CORRECT answer is (d) anionic hydrolysis

Explanation: The aqueous solution of a SALT of a weak acid and strong base is alkaline, DUE to the anionic hydrolysis and aqueous solution of a salt of a strong acid and weak base is acidic, due to CATIONIC hydrolysis with dilution DEGREE of hydrolysis increases.

The correct answer is (C) KW/KaKb

Easiest explanation: The hydrolysis constant of a WEAK ACID and weak base is KW/KaKb, the degree of hydrolysis is √KW/KaKb and the pH of the solution is given by 1/2pKW + 1/2pKa – 1/2pKb. An example of a salt of a weak acid and a weak base is CH3COOHNH4.

Right choice is (b) hydrolysis

Easiest EXPLANATION: Salts are strong electrolytes and on dissolution in WATER split up into IONS. Which react with hydrogen ions are HYDROXIDE ions furnished by water YIELDING an acidic or basic solution. This process is called salt hydrolysis and is the reverse process of neutralization.

Correct OPTION is (a) Normal

Easy explanation: Normal salts LIKE NaCl are obtained by COMPLETE neutralization of an acid with a BASE. Acidic salts are formed by incomplete neutralization of polybasic acids and basic salts are formed by incomplete neutralization of poly acidic base. Double salts are formed by the combination of two simple salts and exist only in the solid state.

Right CHOICE is (a) salts

Easy explanation: Salts are the products of the reaction between an acid and a base, these TYPE of reactions are called neutralization reactions. There are many TYPES of salts like NORMAL, acidic, basic, double, COMPLEX and mixed salts.

Right choice is (c) blood plasma

For EXPLANATION I WOULD say: Acids always have a pH below 7 and bases have a pH of above 7, while neutral COMPOUNDS have a pH of 7. Here gastric juice, VINEGAR, and lemon are acids, so they have a pH of below 7, but blood plasma is a base. It has a pH greater than 7.

Correct option is (a) 14

The best EXPLANATION: We know that the ionization constant of water at 298 k is given by [H3O^+][OH^–] =1 x 10^-14/mol^2L^2. PKW = pH + pOH = -log[H3O^+] – log[OH^–] = -log[H3O^+][OH^–] = -log10^-14 = log10^14 = 14. Therefore pKW at 298 k is 14.

Correct OPTION is (a) true

For explanation I WOULD say: The ionization product of water is GIVEN by [H3O^+][OH^–] =1 x 10^-14/mol^2L^2 at 298 k, the product of the concentration of hydronium IONS and hydroxyl ions in pure water. Concentrations increase with temperature, so the ionization constant of water increases with increase in temperature.

Right answer is (b) [H^+] = 10^-pH

To EXPLAIN I WOULD say: pH is defined as the negative logarithm of hydrogen ION concentration that is pH = -log[H^+]. By rearranging pH in terms of concentration of hydrogen ions, we get [H^+] = 10^-pH. pH MEANS POTENTIAL of hydrogen.

Right option is (d) 1 x 10^-14/mol^2L^2

Explanation: Ionic PRODUCT is a product of the concentration of hydronium ions and hydroxyl ions in PURE water, which REMAINS constant at a PARTICULAR temperature. It is SYMBOLIZED as KW and is equal to1 x 10^-14/mol^2L^2.

Right answer is (d) hydroxide ion

Easiest explanation: Lewis acids are molecules with an incomplete octet of CENTRAL ATOMS like ALUMINIUM CHLORIDE, simple CATIONS like sodium ion, and molecules in which the central atom has vacant d-orbital like sulphur tetrafluoride, but hydroxide ion is a negatively charged species. So it is not a Lewis acid.

Correct OPTION is (b) base, acid

To elaborate: Water acts as a base in the PRESENCE of HYDROCHLORIC acid and acts as an acid in the presence of ammonia. ACCORDING to bronsted, acid is a chemical substance that can donate a PROTON and base can accept a Proton from other substances.

Right choice is (a) true

Explanation: According to the BRONSTED concept of acids and bases, ACID is a chemical substance that can donate a PROTON to some other substance and base is a chemical substance that can ACCEPT a Proton from other substance.

Correct option is (b) HClO4

Easiest explanation: HClO4 which is called Perchloric acid, is the strongest HYDRACID known and HCN called FORMONITRILE, is the weakest hydracid known. CsOH called CAESIUM Hydroxide is the strongest base known.

The correct option is (b) water and HYDROXIDE ion

For explanation I would say: According to BRONSTED concept of acids and bases, the two conjugate pairs in the above-given equation NH3 + H2O \(\rightleftharpoons\) NH4 + OH^– are AMMONIA – ammonium Ion and water – Hydroxide ion. Here acids are water and ammonium ion.

The CORRECT answer is (a) True

The explanation: Lewis acid is a chemical substance which can ACCEPT a pair of electrons. Examples are MOLECULES with an incomplete octet of central atom SIMPLE cations like silver ION molecules in West central atom has vacant d orbitals.

Correct answer is (c) PROTONIC ACIDS

For explanation I would say: The major limitations of the Lewis concept is that it does not explain the behaviour of protonic acids such as hydrochloric acid, sulphuric acid and NITRIC acid. It also does not PREDICT the magnitude of the relative strength of acids and bases.

Right choice is (a) ammonia

For explanation I would say: Lewis BASE is a CHEMICAL substance which can DONATE a PAIR of electrons. Examples are neutral molecules containing lone pairs like ammonia, negatively CHARGED species and the ligands in coordination species.

Correct CHOICE is (d) protophilic

To explain: Amphoteric or amphiprotic substance or ampholytes are the substances which ACT as an acid as well as a base and EXAMPLE for this is WATER. It acts as an acid with Ammonia and base with acetic acid.

Right answer is (B) weak conjugate base

For EXPLANATION: As per the conjugate pairs in the bronsted concept of acid and bases, STRONG acid has a weak conjugate base and weak acid has a strong conjugate base. The strong base has weak conjugate acid and the weak base has strong conjugate acid.

The correct option is (a) protongenic

Easiest explanation: According to the BRONSTED concept of ACIDS and bases, an acid that is a Proton Donor is proton genic and a BASE that is a Proton ACCEPTOR is protophilic, while an AMPHOTERIC substance is both base and acid.

Right choice is (a) true

Easiest explanation: The MAJOR drawback of Arrhenius theory is that it fails to explain the acidic and basic behaviour in non-aqueous SOLUTIONS. It cannot explain the acidic character of ALUMINIUM chloride, Boron fluoride and basic character of NH3 PH3.

Right choice is (a) acid

Best EXPLANATION: According to the ARRHENIUS concept of acids and bases, an acid is a chemical SUBSTANCE which dissociates in aqueous SOLUTION to GIVE hydrogen ions or hydronium ions. Therefore HCl is an Arrhenius acid.

The correct choice is (d) bitter in taste

For explanation I WOULD SAY: According to Robert Boyle, acids are the substances which have a sour taste, turns blue Litmus red, liberate hydrogen with metals conduct ELECTRICITY in aqueous SOLUTION and NEUTRALIZE bases. They do not have a bitter taste.

The correct CHOICE is (b) no

Easy explanation: Michael Faraday classified SUBSTANCES into two categories; one is ELECTROLYTES and nonelectrolytes, nonelectrolytes do not DISSOCIATE into ions in a solution. So they do not conduct electricity.