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🔬💡 Master Acids, Bases & Salts: Essential MCQs for FSC, MDCAT & ECAT Aptitude to Ace Your Chemistry Exam! 🚀
The Ultimate Guide for Chemistry Enthusiasts! 🌟🧪
1️⃣ Corrosive effect on skin is caused by:
🟦 A) Acid
🟩 B) Base
🟪 C) Salt
🟨 D) Both A and B
2️⃣ Preservatives are used to preserve:
🟦 A) Acid
🟩 B) Base
🟪 C) Food
🟨 D) Water
3️⃣ Which of the following is NOT an Arrhenius acid?
🟦 A) HCl
🟩 B) CO₂
🟪 C) HNO₃
🟨 D) H₂SO₄
4️⃣ NH₃ can be a base according to:
🟦 A) Arrhenius theory
🟩 B) Bronsted-Lowry theory
🟪 C) Lewis theory
🟨 D) Both B and C
5️⃣ Which of the following is a Lewis base?
🟦 A) HNO₃
🟩 B) CN⁻
🟪 C) HCl
🟨 D) AlCl₃
6️⃣ A substance that can donate a pair of electrons to form a coordinate covalent bond:
🟦 A) Lewis acid
🟩 B) Bronsted-Lowry acid
🟪 C) Bronsted-Lowry base
🟨 D) Lewis base
7️⃣ If the pH value is greater than 7, then the solution is:
🟦 A) Acidic
🟩 B) Basic
🟪 C) Amphoteric
🟨 D) Neutral
8️⃣ Salt among the following is:
🟦 A) HCl
🟩 B) KCl
🟪 C) HNO₃
🟨 D) H₂SO₄
9️⃣ Substances that react with both acids and bases are called:
🟦 A) Conjugate base
🟩 B) Conjugate acids
🟪 C) Amphoteric substances
🟨 D) Buffers
🔟 The reaction of acid and base to form salt and water is called:
🟦 A) Hydration
🟩 B) Neutralization
🟪 C) Hydrolysis
🟨 D) Both A and C
1️⃣1️⃣ The formula of Epsom salt is:
🟦 A) Na₂CO₃
🟩 B) MgSO₄·7H₂O
🟪 C) Na₂CO₃·10H₂O
🟨 D) NaHCO₃
1️⃣2️⃣ A solution whose strength is known is called:
🟦 A) Molar solution
🟩 B) Standard solution
🟪 C) Normal solution
🟨 D) None of them
1️⃣3️⃣ If the H⁺ ion concentration of a solution is 1 x 10⁻¹⁴ M, the solution is:
🟦 A) Molar solution
🟩 B) Acidic solution
🟪 C) Neutral solution
🟨 D) Basic solution
1️⃣4️⃣ If the OH⁻ ion concentration of a solution is 1 x 10⁻¹⁰ M, the solution is:
🟦 A) Basic
🟩 B) Acidic
🟪 C) Neutral
🟨 D) Normal
1️⃣5️⃣ The solution whose pH is 6, then its H⁺ ion concentration is:
🟦 A) 1 x 10⁻⁴ M
🟩 B) 1 x 10⁻⁶ M
🟪 C) 1 x 10⁻¹⁴ M
🟨 D) 1 x 10⁻² M
1️⃣6️⃣ ………… is the process by which we can determine the concentration of an unknown solution with the help of a standard solution:
🟦 A) Titration
🟩 B) Sublimation
🟪 C) Crystallization
🟨 D) None of them
1️⃣7️⃣ The volume of a pipette is generally:
🟦 A) 10 ml or cm³
🟩 B) 20 ml or cm³
🟪 C) 25 ml or cm³
🟨 D) 50 ml or cm³
1️⃣8️⃣ The solution whose H⁺ ion concentration is 1 x 10⁻⁴ M, then its pH is:
🟦 A) 4
🟩 B) 8
🟪 C) 7
🟨 D) 10
1️⃣9️⃣ The pH value of human blood is:
🟦 A) 7.35-7.45
🟩 B) 7.8
🟪 C) 7.2
🟨 D) 7.0
2️⃣0️⃣ The formula of sodium hydrogencarbonate is:
🟦 A) Na₂CO₃
🟩 B) NaHCO₃
🟪 C) Na₂CO₃·10H₂O
🟨 D) Na₂CO₃·6H₂O
2️⃣1️⃣ The pH value of distilled water is:
🟦 A) 1
🟩 B) 4
🟪 C) 7
🟨 D) 14
2️⃣2️⃣ Chemically strong acid is:
🟦 A) Acetic acid
🟩 B) Nitric acid
🟪 C) Hydrochloric acid
🟨 D) Sulphuric acid
2️⃣3️⃣ What is the pH of a neutral solution?
🟦 A) 0
🟩 B) 1
🟪 C) 7
🟨 D) 14
2️⃣4️⃣ The pH value of saliva is:
🟦 A) 4.2
🟩 B) 6.5
🟪 C) 7.0
🟨 D) 7.8
2️⃣5️⃣ Which of the following substances is called proton donor?
🟦 A) Acids
🟩 B) Bases
🟪 C) Salts
🟨 D) Alkali
2️⃣6️⃣ It is a proton donor:
🟦 A) Acid
🟩 B) Base
🟪 C) Salt
🟨 D) Alkali
2️⃣7️⃣ A species formed by the loss of a proton from an acid is called a…………..
🟦 A) Lewis base
🟩 B) Conjugate base
🟪 C) Conjugate acid
🟨 D) Arrhenius acid
2️⃣8️⃣ A species formed by the addition of a proton to a base is called ………..
🟦 A) Lewis base
🟩 B) Conjugate base
🟪 C) Conjugate acid
🟨 D) Arrhenius acid
2️⃣9️⃣ In the reaction: NH₃ + HCl → NH₄⁺ + Cl⁻; which one is conjugate base?
🟦 A) NH₃
🟩 B) HCl
🟪 C) Cl⁻
🟨 D) NH₄⁺
3️⃣0️⃣ In the reaction: CH₃COOH + H₂O ⇌ H₃O⁺ + CH₃COO⁻; which one is conjugate base?
🟦 A) H₃O⁺
🟩 B) H₂O
🟪 C) CH₃COO⁻
🟨 D) CH₃COOH
3️⃣1️⃣ In the reaction: NH₃ + H₂O ⇌ NH₄⁺ + OH⁻, which one is conjugate acid?
🟦 A) NH₃
🟩 B) H₂O
🟪 C) OH⁻
🟨 D) NH₄⁺
3️⃣2️⃣ The conjugate base of a strong acid is always a……………
🟦 A) Weak base
🟩 B) Weak acid
🟪 C) Strong acid
🟨 D) Strong base
3️⃣3️⃣ The conjugate acid of a strong base is always a……………
🟦 A) Weak base
🟩 B) Weak acid
🟪 C) Strong acid
🟨 D) Strong base
3️⃣4️⃣ HCl is a strong acid since its conjugate base Cl⁻ is a…………..
🟦 A) Weak base
🟩 B) Weak acid
🟪 C) Strong acid
🟨 D) Strong base
3️⃣5️⃣ Which one of the following is a monoprotic acid?
🟦 A) H₂C₂O₄
🟩 B) H₂SO₄
🟪 C) H₄C₂O₂
🟨 D) C₆H₄(COOH)₂
3️⃣6️⃣ Which one of the following is NOT a dibasic acid?
🟦 A) H₂C₂O₄
🟩 B) H–HSO₄
🟪 C) H₆C₄O₄ (succinic acid)
🟨 D) H₃BO₃
3️⃣7️⃣ Which one is NOT a Lewis base?
🟦 A) NH₃
🟩 B) NaNH₂
🟪 C) C₂H₅OH
🟨 D) AlCl₃
3️⃣8️⃣ Which one is NOT a Lewis acid?
🟦 A) AlCl₃
🟩 B) FeCl₃
🟪 C) BF₃
🟨 D) NH₃
3️⃣9️⃣ The value of ionic product (Kw) of water at 25ºC is equal to:
🟦 A) 1 x 10¹⁴
🟩 B) 1 x 10⁻¹⁴
🟪 C) 1 x 10⁻⁷
🟨 D) 1 x 10⁻¹⁰
4️⃣0️⃣ The sum of pH and pOH of any solution at 25ºC is:
🟦 A) 7
🟩 B) 9
🟪 C) 14
🟨 D) 3
4️⃣1️⃣ A solution which contains [H⁺] concentration equal to 10⁻⁷ M is said to be:
🟦 A) Acidic
🟩 B) Neutral
🟪 C) Basic
🟨 D) Alkaline
4️⃣2️⃣ A solution which contains [H⁺] concentration less than 10⁻⁷ M is said to be:
🟦 A) Acidic
🟩 B) Basic
🟪 C) Alkaline
🟨 D) Neutral
4️⃣3️⃣ A solution which contains [H⁺] concentration greater than 10⁻⁷ M is said to be:
🟦 A) Acidic
🟩 B) Basic
🟪 C) Neutral
🟨 D) Amphoteric
4️⃣4️⃣ The hydroxyl ion concentration in a solution having pH value 3 will be:
🟦 A) 10⁻¹⁴ M
🟩 B) 10⁻⁷ M
🟪 C) 10⁻¹² M
🟨 D) 10⁻¹¹ M
4️⃣5️⃣ The hydroxyl ion concentration in a solution having pH value 12 will be:
🟦 A) 10⁻² M
🟩 B) 10⁻⁷ M
🟪 C) 10⁻¹² M
🟨 D) 10⁻¹⁰ M
4️⃣6️⃣ The pH of a solution with hydrogen ion concentration of 1 x 10⁻³ is:
🟦 A) 3
🟩 B) 2
🟪 C) 1
🟨 D) 11
4️⃣7️⃣ The pH of a solution that has 0.00001 mole of H⁺ per liter of solution is:
🟦 A) 2
🟩 B) 5
🟪 C) 4
🟨 D) 9
4️⃣8️⃣ Which one of the following substances has pH value less than 7?
🟦 A) Milk of magnesia
🟩 B) Sea water
🟪 C) Blood
🟨 D) Milk
4️⃣9️⃣ Which one of the following substances has pH value more than 7?
🟦 A) Vinegar
🟩 B) Sodium carbonate
🟪 C) Sulphuric acid
🟨 D) Soda water
5️⃣0️⃣ Which of the following salts has no water of crystallization?
🟦 A) Gypsum
🟩 B) Blue vitriol
🟪 C) Baking soda
🟨 D) Washing soda
5️⃣1️⃣ Metal carbonate on reaction with dilute acid releases:
🟦 A) CO₂
🟩 B) H₂O
🟪 C) CO
🟨 D) H₂
5️⃣2️⃣ In general, dissolution of acid or base in water is:
🟦 A) Exothermic
🟩 B) Endothermic
🟪 C) Violent
🟨 D) None of these
5️⃣3️⃣ Hydrogen ions produced by acid exist in which of the following form?
🟦 A) Hydroxonium ions
🟩 B) Hydrogen
🟪 C) Water ions
🟨 D) Hydroxide ions
5️⃣4️⃣ The acid found in an ant sting is:
🟦 A) Tartaric acid
🟩 B) Citric acid
🟪 C) Methanoic acid
🟨 D) Acetic acid
5️⃣5️⃣ Which one of the following acids is not monoprotic?
🟦 A) H₃BO₃
🟩 B) CH₃COOH
🟪 C) HNO₃
🟨 D) HO-SO₃H
5️⃣6️⃣ Universal indicator turns red in:
🟦 A) Acid solution
🟩 B) Alkaline solution
🟪 C) Neutral solution
🟨 D) Basic solution
5️⃣7️⃣ The pH of milk is:
🟦 A) 7.3
🟩 B) 6.0
🟪 C) 6.3
🟨 D) 5.6
5️⃣8️⃣ 7.3 is the pH of:
🟦 A) Human blood
🟩 B) Tomato juice
🟪 C) Vinegar
🟨 D) Milk
5️⃣9️⃣ The acids which contain two or more acidic hydrogens are called:
🟦 A) Monoprotic
🟩 B) Diprotic
🟪 C) Triprotic
🟨 D) Polyprotic
6️⃣0️⃣ The basicity refers to the number of ionizable ………… ions:
🟦 A) H⁺
🟩 B) OH⁻
🟪 C) H₂
🟨 D) Both A and B
6️⃣1️⃣ If [H⁺] ions concentration of solution is 1 x 10⁰ M, then the solution is strongly:
🟦 A) Acidic
🟩 B) Basic
🟪 C) Neutral
🟨 D) Amphoteric
6️⃣2️⃣ Universal indicator turns green in:
🟦 A) Neutral solution
🟩 B) Alkaline solution
🟪 C) Acid solution
🟨 D) Basic solution
6️⃣3️⃣ The pH of saliva is:
🟦 A) 7.3
🟩 B) 6.0
🟪 C) 6.3
🟨 D) 5.6
6️⃣4️⃣ Which one of the following is not a strong acid?
🟦 A) HF
🟩 B) HNO₃
🟪 C) HCl
🟨 D) H₂SO₄
6️⃣5️⃣ What will be the value of pH of 10⁻⁵ M NaOH solution?
🟦 A) 5
🟩 B) 8
🟪 C) 9
🟨 D) 10
6️⃣6️⃣ What is the pH of a 0.00001 molar HCl solution?
🟦 A) 1
🟩 B) 9
🟪 C) 5
🟨 D) 4
6️⃣7️⃣ The pH of milk of magnesia is:
🟦 A) 1.2%
🟩 B) 1.4%
🟪 C) 1.9%
🟨 D) 2.1%
6️⃣9️⃣ What is the pOH of a solution whose pH is 8?
🟦 A) 6
🟩 B) 10
🟪 C) 4
🟨 D) 2
7️⃣0️⃣ Lime water turns milky when carbon dioxide is passed due to the formation of ______.
🟦 A) CaCO₃
🟩 B) CO₂
🟪 C) CaO
🟨 D) CaSO₄
7️⃣1️⃣ Which ion is not present in dilute sulfuric acid?
🟦 A) H⁺
🟩 B) OH⁻
🟪 C) SO₃²⁻
🟨 D) SO₄²⁻
7️⃣2️⃣ Which oxide will produce the solution with the highest pH when it is mixed with water?
🟦 A) Al₂O₃
🟩 B) SO₂
🟪 C) Na₂O
🟨 D) CO₂
7️⃣3️⃣ Metal carbonate on reaction with dilute acid releases:
🟦 A) H₂O
🟩 B) H₂
🟪 C) CO₂
🟨 D) CO
7️⃣4️⃣ Identify the conjugate acid of SO₄²⁻
🟦 A) H₂SO₄
🟩 B) SO₃²⁻
🟪 C) HSO₄⁻
🟨 D) H₂SO₃
7️⃣5️⃣ Which one of the following is a weak acid?
🟦 A) HF
🟩 B) HClO₃
🟪 C) HNO₃
🟨 D) HI
7️⃣6️⃣ Which one of the following is a STRONG electrolyte?
🟦 A) HF
🟩 B) KF
🟪 C) HNO₂
🟨 D) (CH₃)₃N
7️⃣7️⃣ Which of the following is classified as a conjugate acid-base pair?
🟦 A) HCl/NaOH
🟩 B) H₃O⁺
🟪 C) O₂/H₂O
🟨 D) H⁺/Cl⁻
7️⃣8️⃣ pOH of pure water at 25ºC is _____________.
🟦 A) 7
🟩 B) 14
🟪 C) 0
🟨 D) -7
7️⃣9️⃣ Acid + Metal oxide → -----------
🟦 A) Base + water
🟩 B) Base + salt
🟪 C) Salt + water
🟨 D) Metal + salt
8️⃣0️⃣ What is formed by the reaction of a non-metal oxide with water?
🟦 A) Acid
🟩 B) Base
🟪 C) Salt
🟨 D) Metal
8️⃣1️⃣ Which of the following solutions is most basic?
🟦 A) pH = 10.6
🟩 B) pH = 11.5
🟪 C) pH = 9.3
🟨 D) pH = 8.2
8️⃣2️⃣ What is used to measure the exact pH of an aqueous solution?
🟦 A) pH paper
🟩 B) Universal indicator
🟪 C) pH meter
🟨 D) Litmus paper
8️⃣3️⃣ Which of the following substances is an antacid?
🟦 A) NaCl
🟩 B) Mg(OH)₂
🟪 C) HCl
🟨 D) H₂SO₄
8️⃣4️⃣ The pH values of solutions A, B, C, and D are 1.9, 2.5, 2.1, and 3.0, respectively. Their order of acidity will be:
🟦 A) D < C < B < A
🟩 B) D > C > B > A
🟪 C) A < C < B < D
🟨 D) D < B < C < A
8️⃣5️⃣ Which solution will be basic?
🟦 A) [H₃O⁺] = 10⁻⁵ M
🟩 B) [H₃O⁺] = 10⁻¹² M
🟪 C) [H₃O⁺] = 10⁻⁷ M
🟨 D) [H₃O⁺] = 10⁻⁴ M
8️⃣6️⃣ The bond between H⁺ and H₂O in H₃O⁺ is...
🟦 A) Coordinate covalent
🟩 B) Covalent
🟪 C) Metallic
🟨 D) Ionic
8️⃣7️⃣ The hydroxonium ion is:
🟦 A) Hydrated proton
🟩 B) Protonated water molecules
🟪 C) Both of them
🟨 D) None of them
8️⃣8️⃣ Whose definition of acids and bases emphasizes the role of protons?
🟦 A) Brønsted and Lowry
🟩 B) Arrhenius
🟪 C) Faraday
🟨 D) Lewis
8️⃣9️⃣ An electron-pair acceptor is a:
🟦 A) Lewis base
🟩 B) Brønsted-Lowry base
🟪 C) Lewis acid
🟨 D) Traditional acid
9️⃣0️⃣ What is the pH of 1 x 10⁻⁴ M HCl solution?
🟦 A) 4
🟩 B) 10
🟪 C) 8
🟨 D) 6
9️⃣1️⃣ What is the pH of a 1 x 10⁻⁵ M KOH solution?
🟦 A) 3
🟩 B) 5
🟪 C) 9
🟨 D) 11
9️⃣2️⃣ Which are the correct products for these reactants: H₂SO₄ + NaOH?
🟦 A) Na₂SO₄ + H₂O
🟩 B) Na₂SO₄ + OH⁻
🟪 C) NaHSO₄ + H₂O
🟨 D) Both A and C
9️⃣3️⃣ Which element is always present in an Arrhenius acid?
🟦 A) Nitrogen
🟩 B) Hydrogen
🟪 C) Oxygen
🟨 D) None of these
9️⃣4️⃣ Which one of the following is a strong electrolyte?
🟦 A) HF
🟩 B) KF
🟪 C) HNO₂
🟨 D) H₂O
9️⃣5️⃣ The conjugate base of HSO₄⁻ is:
🟦 A) H₂SO₄
🟩 B) H₃SO₄⁺
🟪 C) SO₄²⁻
🟨 D) HSO₄⁺
9️⃣6️⃣ Which of the given is a strong base?
🟦 A) Potassium hydroxide
🟩 B) Magnesium hydroxide
🟪 C) Ammonium hydroxide
🟨 D) Calcium hydroxide
9️⃣7️⃣ A Brønsted-Lowry base is defined as:
🟦 A) A hydroxide acceptor
🟩 B) An electron pair acceptor
🟪 C) A proton acceptor
🟨 D) A hydroxide donor
9️⃣8️⃣ The conjugate acid of HSO₄⁻ is:
🟦 A) H₂SO₄
🟩 B) HSO₄⁺
🟪 C) SO₄²⁻
🟨 D) HSO₃⁺
9️⃣9️⃣ According to the Arrhenius acid-base theory, in a neutralization reaction, which molecule is formed?
🟦 A) CO₂
🟩 B) H₂O₂
🟪 C) H₂O
🟨 D) H₂
1️⃣0️⃣0️⃣ The conjugate acid of HPO₃²⁻ is:
🟦 A) HPO₃²⁻
🟩 B) H₂PO₃¹⁻
🟪 C) PO₃³⁻
🟨 D) H₃PO₃
1️⃣0️⃣1️⃣ The conjugate base of NH₃ is:
🟦 A) NH₄⁺
🟩 B) NH₂⁻
🟪 C) NH₂⁻
🟨 D) None of them
1️⃣0️⃣2️⃣ A conjugate acid forms a conjugate base by ……. of a proton:
🟦 A) Accepting
🟩 B) Donating
🟪 C) Gaining
🟨 D) None of them
1️⃣0️⃣3️⃣ A strong base would have a ……… conjugate acid:
🟦 A) Strong
🟩 B) Very strong
🟪 C) Weak
🟨 D) None of them
1️⃣0️⃣4️⃣ The conjugate acid of O²⁻ is:
🟦 A) OH⁻
🟩 B) H₂O
🟪 C) H₃O⁺
🟨 D) None of them
1️⃣0️⃣5️⃣ …… acid-base theory cannot define that NH₃ is a base:
🟦 A) Lewis
🟩 B) Brønsted-Lowry
🟪 C) Arrhenius
🟨 D) None of them
1️⃣0️⃣6️⃣ HSO₄⁻ is the conjugate acid of:
🟦 A) H₂SO₄
🟩 B) SO₄²⁻
🟪 C) H₂O
🟨 D) None of them
1️⃣0️⃣7️⃣ Which of these species will act as a Lewis acid?
🟦 A) NH₃
🟩 B) H₂O
🟪 C) NH₄⁺
🟨 D) BF₃
1️⃣0️⃣8️⃣ The substance whose aqueous solution changes the blue litmus to red:
🟦 A) Acids
🟩 B) Bases
🟪 C) Salts
🟨 D) Neutral
1️⃣0️⃣9️⃣ The substances having a tendency to lose one or more protons are called:
🟦 A) Acids
🟩 B) Bases
🟪 C) Salts
🟨 D) Neutral
1️⃣1️⃣0️⃣ The substance which donates a pair of electrons for bond formation is known as:
🟦 A) Acids
🟩 B) Bases
🟪 C) Salts
🟨 D) Neutral
1️⃣1️⃣1️⃣ When equivalent quantities of acid and base are mixed, salt and water are formed, the reaction is termed as:
🟦 A) Hydration
🟩 B) Hydrolysis
🟪 C) Neutralization
🟨 D) None of these
1️⃣1️⃣2️⃣ The acids which contain one acidic hydrogen are called:
🟦 A) Diprotic
🟩 B) Monoprotic
🟪 C) Triprotic
🟨 D) Polyprotic
1️⃣1️⃣3️⃣ The number of acidic hydrogen atoms present in a molecule of an acid is called:
🟦 A) Acidity
🟩 B) Basicity
🟪 C) Neutrality
🟨 D) Hydrolysis
1️⃣1️⃣4️⃣ The number of replaceable OH⁻ ions present in a molecule of base is called:
🟦 A) Acidity
🟩 B) Basicity
🟪 C) Neutrality
🟨 D) Hydrolysis
1️⃣1️⃣5️⃣ An ionic compound that is formed when an acid neutralizes a base is called:
🟦 A) Acids
🟩 B) Bases
🟪 C) Salts
🟨 D) Indicator
1️⃣1️⃣6️⃣ The formula of washing soda is:
🟦 A) Na₂CO₃
🟩 B) Na₂CO₃·6H₂O
🟪 C) Na₂CO₃·10H₂O
🟨 D) NaHCO₃
1️⃣1️⃣7️⃣ The formula of baking soda is:
🟦 A) Na₂CO₃
🟩 B) Na₂CO₃·6H₂O
🟪 C) Na₂CO₃·10H₂O
🟨 D) NaHCO₃
🌟 🔑 Answers & Explanations for MCQs on Acids, Bases & Salts 🌟
1️⃣ Answer: 🟨 D) Both A and B
Reason: Acids and bases both cause corrosive damage to the skin.
2️⃣ Answer: 🟪 C) Food
Reason: Preservatives are primarily used to prevent food spoilage by inhibiting microbial growth.
3️⃣Answer: 🟩 B) CO₂
Reason: CO₂ is not an Arrhenius acid because it doesn't release H⁺ ions directly in water.
4️⃣ Answer: 🟨 D) Both B and C
Reason: According to Bronsted-Lowry, NH₃ can accept a proton, and according to Lewis theory, it can donate a pair of electrons.
5️⃣Answer: 🟩 B) CN⁻
Reason: CN⁻ is a Lewis base because it donates a pair of electrons.
6️⃣ Answer: 🟨 D) Lewis base
Reason: A Lewis base donates an electron pair to form a coordinate covalent bond.
7️⃣ Answer: 🟩 B) Basic
Reason: pH > 7 indicates a basic (alkaline) solution.
8️⃣Answer: 🟩 B) KCl
Reason: KCl is a neutral salt formed by the reaction of a strong acid (HCl) and a strong base (KOH).
9️⃣ Answer: 🟪 C) Amphotetic substances
Reason: Amphotetic substances can act as both acids and bases depending on the conditions.
1️⃣0️⃣ Answer: 🟩 B) Neutralization
Reason: Neutralization is the reaction between an acid and a base to form salt and water.
1️⃣1️⃣ Answer: 🟩 B) MgSO₄·7H₂O
Reason: Epsom salt is hydrated magnesium sulfate, MgSO₄·7H₂O.
1️⃣2️⃣ Answer: 🟩 B) Standard solution
Reason: A standard solution has a known concentration and is used in titrations.
1️⃣3️⃣ Answer: 🟪 C) Neutral solution
Reason: A pH of 7 (H⁺ = 10⁻¹⁴ M) indicates a neutral solution.
1️⃣4️⃣ Answer: 🟦 A) Basic
Reason: The concentration of OH⁻ being lower than 10⁻⁷ M indicates the solution is basic.
1️⃣5️⃣ Answer: 🟩 B) 1 x 10⁻⁶ M
Reason: pH = -log[H⁺], so a pH of 6 corresponds to a H⁺ ion concentration of 10⁻⁶ M.
1️⃣6️⃣ Answer: 🟦 A) Titration
Reason: Titration is used to determine the concentration of an unknown solution by reacting it with a standard solution.
1️⃣7️⃣ Answer: 🟪 C) 25 ml or cm³
Reason: 25 ml is the most common volume for a pipette used in labs.
1️⃣8️⃣ Answer: 🟦 A) 4
Reason: pH = -log[H⁺], so for 1 x 10⁻⁴ M, pH = 4.
1️⃣ 9️⃣Answer: 🟦 A) 7.35-7.45
Reason: The pH of human blood is slightly alkaline, typically between 7.35 and 7.45.
2️⃣0️⃣ Answer: 🟩 B) NaHCO₃
Reason: Sodium hydrogencarbonate is also known as baking soda, with the formula NaHCO₃.
2️⃣1️⃣ Answer: 🟪 C) 7
Reason: Distilled water is neutral, so its pH is 7.
2️⃣2️⃣ Answer: 🟩 B) Nitric acid
Reason: Nitric acid (HNO₃) is a strong acid because it ionizes completely in water.
2️⃣3️⃣ Answer: 🟪 C) 7
Reason: A neutral solution has a pH of 7, as seen in pure water.
2️⃣4️⃣ Answer: 🟩 B) 6.5
Reason: Saliva has a slightly acidic pH of around 6.5, which helps with digestion.
2️⃣5️⃣ Answer: 🟦 A) Acids
Reason: Acids are proton donors according to Bronsted-Lowry theory.
2️⃣6️⃣ Answer: 🟦 A) Acid
Reason: Acids donate protons (H⁺ ions) in chemical reactions.
2️⃣7️⃣ Answer: 🟩 B) Conjugate base
Reason: A conjugate base is formed after an acid loses a proton.
2️⃣8️⃣ Answer: 🟪 C) Conjugate acid
Reason: When a base accepts a proton, it forms a conjugate acid.
2️⃣9️⃣ Answer: 🟪 C) Cl⁻
Reason: In the reaction, NH₃ acts as a base and HCl as an acid, with Cl⁻ being the conjugate base.
3️⃣0️⃣ Answer: 🟪 C) CH₃COO⁻
Reason: CH₃COO⁻ is the conjugate base of CH₃COOH (acetic acid).
3️⃣1️⃣ Answer: 🟨 D) NH₄⁺
Reason: NH₄⁺ is the conjugate acid formed when NH₃ accepts a proton.
3️⃣2️⃣ Answer: 🟦 A) Weak base
Reason: The conjugate base of a strong acid is typically weak because it does not easily accept protons.
3️⃣3️⃣ Answer: 🟦 A) Weak base
Reason: The conjugate acid of a strong base is a weak acid, as strong bases do not readily donate protons.
3️⃣4️⃣ Answer: 🟦 A) Weak base
Reason: The conjugate base of a strong acid, like Cl⁻, is weak and does not accept protons easily.
3️⃣5️⃣ Answer: 🟦 A) H₂C₂O₄
Reason: Oxalic acid (H₂C₂O₄) is monoprotic because it can donate only one proton.
3️⃣6️⃣ Answer: 🟨 D) H₃BO₃
Reason: Boric acid (H₃BO₃) is not dibasic; it is a weak acid that does not release two protons.
3️⃣7️⃣ Answer: 🟨 D) AlCl₃
Reason: AlCl₃ is a Lewis acid, not a base. It accepts electron pairs but does not donate them.
3️⃣8️⃣ Answer: 🟨 D) NH₃
Reason: NH₃ is a Lewis base (it donates electron pairs) and is not a Lewis acid.
3️⃣9️⃣ Answer: 🟩 B) 1 x 10⁻¹⁴
Reason: At 25ºC, the ion product of water (Kw) is 1 x 10⁻¹⁴.
4️⃣0️⃣ Answer: 🟪 C) 14
Reason: The sum of pH and pOH is always 14 at 25ºC, as per the water dissociation constant.
4️⃣1️⃣ Answer: 🟩 B) Neutral
Reason: A solution with [H⁺] = 10⁻⁷ M is neutral, which corresponds to a pH of 7.
4️⃣2️⃣ Answer: 🟩 B) Basic
Reason: A solution with [H⁺] less than 10⁻⁷ M has a pH greater than 7, making it basic or alkaline.
4️⃣3️⃣ Answer: 🟦 A) Acidic
Reason: A solution with [H⁺] greater than 10⁻⁷ M has a pH less than 7, making it acidic.
4️⃣4️⃣ Answer: 🟪 C) 10⁻¹² M
Reason: The hydroxyl ion concentration can be calculated from the relationship pH + pOH = 14. For pH = 3, pOH = 11, which gives an OH⁻ concentration of 10⁻¹¹ M.
4️⃣5️⃣ Answer: 🟨 D) 10⁻¹⁰ M
Reason: A solution with pH = 12 has a pOH = 2, leading to an OH⁻ concentration of 10⁻² M.
4️⃣6️⃣ Answer: 🟦 A) 3
Reason: pH = -log[H⁺], so for 1 x 10⁻³ M, pH = 3.
4️⃣7️⃣ Answer: 🟪 C) 4
Reason: For 0.00001 moles of H⁺ per liter, the pH = 4, as pH = -log[H⁺].
4️⃣8️⃣ Answer: 🟨 D) Milk
Reason: Milk is slightly acidic with a pH value around 6.
4️⃣9️⃣ Answer: 🟩 B) Sodium carbonate
Reason: Sodium carbonate is basic, with a pH higher than 7.
5️⃣0️⃣ Answer: 🟪 C) Baking soda
Reason: Baking soda (NaHCO₃) does not have water of crystallization, unlike the other salts listed.
5️⃣1️⃣ Answer: 🟦 A) CO₂
Reason: When metal carbonates react with dilute acids, carbon dioxide (CO₂) gas is released.
5️⃣2️⃣ Answer: 🟩 B) Endothermic
Reason: The dissolution of many acids and bases in water is endothermic, requiring heat absorption.
5️⃣3️⃣ Answer: 🟦 A) Hydroxonium ions
Reason: Hydrogen ions produced by acids combine with water molecules to form hydroxonium ions (H₃O⁺).
5️⃣4️⃣ Answer: 🟪 C) Methanoic acid
Reason: The acid found in ant stings is methanoic acid (also known as formic acid).
5️⃣5️⃣ Answer: 🟦 A) H₃BO₃
Reason: Boric acid (H₃BO₃) is not monoprotic, as it does not release one proton per molecule.
5️⃣6️⃣ Answer: 🟦 A) Acid solution
Reason: Universal indicator turns red in acidic solutions, indicating a low pH.
5️⃣7️⃣ Answer: 🟩 B) 6.0
Reason: Milk has a slightly acidic pH of about 6.0.
5️⃣8️⃣ Answer: 🟦 A) Human blood
Reason: Human blood has a pH around 7.35 to 7.45, which is slightly alkaline.
5️⃣9️⃣ Answer: 🟩 B) Diprotic
Reason: Diprotic acids, like sulfuric acid, can donate two protons.
6️⃣0️⃣ Answer: 🟦 A) H⁺
Reason: Basicity refers to the number of hydrogen ions (H⁺) an acid can donate in a reaction.
6️⃣1️⃣ Answer: 🟦 A) Acidic
Reason: A solution with [H⁺] concentration of 1 x 10⁰ M is highly acidic, as the concentration of hydrogen ions is very high.
6️⃣2️⃣ Answer: 🟦 A) Neutral solution
Reason: Universal indicator turns green at a neutral pH of 7.
6️⃣3️⃣ Answer: 🟪 C) 6.3
Reason: The pH of saliva typically ranges from 6 to 7, with 6.3 being a common value.
6️⃣4️⃣ Answer: 🟦 A) HF
Reason: HF (hydrofluoric acid) is a weak acid, not a strong acid like the others listed.
6️⃣5️⃣ Answer: 🟪 C) 9
Reason: NaOH is a strong base, and for a 10⁻⁵ M NaOH solution, the pH is 9.
6️⃣6️⃣ Answer: 🟦 A) 1
Reason: The pH of a 0.00001 M HCl solution is 1 because pH = -log[H⁺].
6️⃣7️⃣ Answer: 🟩 B) 1.4%
Reason: The pH of milk of magnesia, a suspension of magnesium hydroxide, is typically around 1.4% on the pH scale.
6️⃣9️⃣ Answer: 🟩 B) 10
Reason: The pOH can be calculated by subtracting the pH from 14. For pH = 8, pOH = 6.
7️⃣0️⃣ Answer: 🟦 A) CaCO₃
Reason: Lime water turns milky due to the formation of calcium carbonate (CaCO₃) when CO₂ is bubbled through it.
7️⃣1️⃣ Answer: 🟩 B) OH⁻
Reason: Dilute sulfuric acid contains H⁺ and SO₄²⁻ ions but does not contain OH⁻ ions, which are characteristic of basic solutions.
7️⃣2️⃣ Answer: 🟪 C) Na₂O
Reason: Sodium oxide (Na₂O) reacts with water to form a strongly basic solution, giving it the highest pH.
7️⃣3️⃣ Answer: 🟦 C) CO₂
Reason: Metal carbonates react with dilute acids to release carbon dioxide (CO₂).
7️⃣4️⃣ Answer: 🟪 C) HSO₄⁻
Reason: The conjugate acid of SO₄²⁻ is HSO₄⁻, formed by the addition of a proton to SO₄²⁻.
7️⃣5️⃣ Answer: 🟦 A) HF
Reason: HF (hydrofluoric acid) is a weak acid compared to the strong acids listed.
7️⃣6️⃣ Answer: 🟩 B) KF
Reason: KF is a strong electrolyte because it dissociates completely in water.
7️⃣7️⃣ Answer: 🟦 A) HCl/NaOH
Reason: HCl and NaOH form a conjugate acid-base pair in a neutralization reaction.
7️⃣8️⃣ Answer: 🟦 A) 7
Reason: Pure water at 25ºC has a pOH of 7 because pH + pOH = 14.
7️⃣9️⃣ Answer: 🟪 C) Salt + water
Reason: When an acid reacts with a metal oxide, the products are a salt and water.
8️⃣0️⃣ Answer: 🟦 A) Acid
Reason: Non-metal oxides (like CO₂, SO₂) form acidic solutions when dissolved in water.
8️⃣1️⃣ Answer: 🟩 B) pH = 11.5
Reason: The higher the pH, the more basic the solution. A pH of 11.5 indicates a strongly basic solution.
8️⃣2️⃣ Answer: 🟪 C) pH meter
Reason: A pH meter gives the most accurate measurement of the exact pH of an aqueous solution.
8️⃣3️⃣ Answer: 🟩 B) Mg(OH)₂
Reason: Magnesium hydroxide (Mg(OH)₂) is commonly used as an antacid to neutralize stomach acid.
8️⃣4️⃣ Answer: 🟩 B) D > C > B > A
Reason: The lower the pH, the more acidic the solution. Thus, the solution with pH 1.9 (A) is the most acidic, and the one with pH 3.0 (D) is the least acidic.
8️⃣5️⃣ Answer: 🟩 B) [H₃O⁺] = 10⁻¹² M
Reason: A solution with [H₃O⁺] concentration of 10⁻¹² M will have a pH greater than 7, indicating that it is basic.
8️⃣6️⃣ Answer: 🟦 A) Coordinate covalent
Reason: In H₃O⁺, the bond between H⁺ and H₂O is coordinate covalent because the shared electrons come from the water molecule.
8️⃣7️⃣ Answer: 🟪 C) Both of them
Reason: Hydroxonium (H₃O⁺) is both a hydrated proton and a protonated water molecule.
8️⃣8️⃣ Answer: 🟦 A) Brønsted and Lowry
Reason: The Brønsted-Lowry theory defines acids and bases in terms of proton (H⁺) donation and acceptance.
8️⃣9️⃣ Answer: 🟪 C) Lewis acid
Reason: A Lewis acid is an electron-pair acceptor, whereas a Lewis base is an electron-pair donor.
9️⃣0️⃣ Answer: 🟦 A) 4
Reason: For a 1 x 10⁻⁴ M HCl solution, the pH is 4 because pH = -log[H⁺].
9️⃣1️⃣ Answer: 🟨 D) 11
Reason: The pH of a KOH solution can be found by calculating pOH = 14 - pH. For a 1 x 10⁻⁵ M KOH solution, the pH = 11.
9️⃣2️⃣ Answer: 🟦 A) Na₂SO₄ + H₂O
Reason: H₂SO₄ + NaOH forms Na₂SO₄ and water in a neutralization reaction.
9️⃣3️⃣ Answer: 🟩 B) Hydrogen
Reason: All Arrhenius acids contain hydrogen, as they donate H⁺ ions in aqueous solution.
9️⃣4️⃣ Answer: 🟩 B) KF
Reason: KF is a strong electrolyte because it dissociates completely in solution.
9️⃣5️⃣ Answer: 🟪 C) SO₄²⁻
Reason: The conjugate base of HSO₄⁻ is SO₄²⁻, formed by the loss of a proton.
9️⃣6️⃣ Answer: 🟦 A) Potassium hydroxide
Reason: Potassium hydroxide (KOH) is a strong base and dissociates completely in water.
9️⃣7️⃣ Answer: 🟪 C) A proton acceptor
Reason: A Brønsted-Lowry base is defined as a proton (H⁺) acceptor.
9️⃣8️⃣ Answer: 🟦 A) H₂SO₄
Reason: The conjugate acid of HSO₄⁻ is H₂SO₄, formed by the addition of a proton.
9️⃣9️⃣ Answer: 🟦 C) H₂O
Reason: According to the Arrhenius theory, a neutralization reaction between an acid and base always forms water (H₂O).
1️⃣0️⃣0️⃣ Answer: 🟩 B) H₂PO₃¹⁻
Reason: The conjugate acid of HPO₃²⁻ is H₂PO₃¹⁻.
1️⃣0️⃣1️⃣ Answer: 🟩 B) NH₂⁻
Reason: The conjugate base of NH₃ (ammonia) is NH₂⁻ (amide ion), formed when NH₃ donates a proton.
1️⃣0️⃣2️⃣ Answer: 🟩 B) Donating
Reason: A conjugate acid donates a proton (H⁺) to form its conjugate base.
1️⃣0️⃣3️⃣ Answer: 🟩 C) Weak
Reason: A strong base has a weak conjugate acid because it easily accepts protons, making its conjugate acid less likely to donate a proton.
1️⃣0️⃣4️⃣ Answer: 🟦 A) OH⁻
Reason: The conjugate acid of O²⁻ (oxide ion) is OH⁻ (hydroxide ion) formed by the addition of a proton.
1️⃣0️⃣5️⃣ Answer: 🟩 C) Arrhenius
Reason: According to the Arrhenius theory, NH₃ cannot be classified as a base because it does not increase the concentration of OH⁻ in water directly.
1️⃣0️⃣6️⃣ Answer: 🟩 B) SO₄²⁻
Reason: HSO₄⁻ (hydrogen sulfate ion) is the conjugate acid of SO₄²⁻ (sulfate ion).
1️⃣0️⃣7️⃣ Answer: 🟨 D) BF₃
Reason: BF₃ is a Lewis acid because it can accept a pair of electrons from a Lewis base.
1️⃣0️⃣8️⃣ Answer: 🟦 A) Acids
Reason: Acids turn blue litmus paper red in an aqueous solution.
1️⃣0️⃣9️⃣ Answer: 🟦 A) Acids
Reason: Substances that tend to lose one or more protons (H⁺) are acids.
1️⃣1️⃣0️⃣ Answer: 🟩 B) Bases
Reason: Bases donate a pair of electrons to form bonds with other species, which is characteristic of a Lewis base.
1️⃣1️⃣1️⃣ Answer: 🟪 C) Neutralization
Reason: The reaction between an acid and a base that produces salt and water is known as neutralization.
1️⃣1️⃣2️⃣ Answer: 🟩 B) Monoprotic
Reason: Monoprotic acids contain one replaceable hydrogen ion (H⁺) per molecule.
1️⃣1️⃣3️⃣ Answer: 🟦 A) Acidity
Reason: Acidity refers to the number of acidic hydrogen atoms present in an acid molecule.
1️⃣1️⃣4️⃣ Answer: 🟩 B) Basicity
Reason: Basicity refers to the number of replaceable hydroxide ions (OH⁻) in a base.
1️⃣1️⃣5️⃣ Answer: 🟪 C) Salts
Reason: An ionic compound formed when an acid neutralizes a base is called a salt.
1️⃣1️⃣6️⃣ Answer: 🟩 B) Na₂CO₃·6H₂O
Reason: Washing soda has the formula Na₂CO₃·6H₂O (sodium carbonate with 6 water molecules of crystallization).
1️⃣1️⃣7️⃣ Answer: 🟨 D) NaHCO₃
Reason: Baking soda is NaHCO₃ (sodium bicarbonate).
🧠
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