Acid, Base and Salt

Corrosive effect on skin is caused by:

Solution

Acids have a corrosive effect on the skin due to their ability to donate protons, which can disrupt tissue structure.

Preservatives are used to preserve:

Solution

Preservatives are commonly used in food to prevent spoilage by inhibiting the growth of bacteria and fungi.

Which of the following is not an Arrhenius acid:

Solution

CO₂ is not an Arrhenius acid because it does not produce \( \text{H}^+ \) ions in aqueous solution.

NH₃ can be a base according to:

Solution

NH₃ can be a base according to both the Bronsted-Lowry theory (as a proton acceptor) and the Lewis theory (as an electron pair donor).

Which of the following is a Lewis base?

Solution

CN⁻ is a Lewis base because it can donate a pair of electrons to form a coordinate covalent bond.

A substance that can donate a pair of electrons to form a coordinate covalent bond:

Solution

A Lewis base can donate a pair of electrons to form a coordinate covalent bond.

If pH value is greater than 7, then the solution is:

Solution

A pH value greater than 7 indicates a basic solution.

Salt among the following is:

Solution

KCl is a salt, formed from the neutralization reaction between an acid and a base.

Substances that react with both acids and bases are called:

Solution

Amphoteric substances can react with both acids and bases.

The reaction of acid and base to form salt and water is called:

Solution

The reaction of an acid and a base to form salt and water is called neutralization.

What happens when an acid is added to blue litmus paper?

Solution

When an acid is added to blue litmus paper, it turns red due to the acidic nature.

Which of the following is not a characteristic of bases?

Solution

Bases turn red litmus blue, not the other way around.

According to Arrhenius theory, acids produce which ion in aqueous solution?

Solution

According to the Arrhenius theory, acids produce \( \text{H}^+ \) ions in aqueous solution.

According to the Brønsted-Lowry theory, a base is a:

Solution

According to the Brønsted-Lowry theory, a base is a proton acceptor.

What is formed when a base accepts a proton?

Solution

When a base accepts a proton, it forms its conjugate acid.

What type of bond is formed by a Lewis acid and base reaction?

Solution

A Lewis acid and base reaction forms a coordinate covalent bond.

Which of the following substances can act both as an acid and a base?

Solution

Water (\( \text{H}_2\text{O} \)) can act both as an acid and a base, making it amphoteric.

What is the ion product constant of water at 25°C?

Solution

The ion product constant of water at 25°C is \(1 \times 10^{-14}\).

What is the pH of pure water at 25°C?

Solution

The pH of pure water at 25°C is 7, indicating it is neutral.

What is used to determine the pH range by changing color?

Solution

Indicators are used to determine the pH range by changing color.

What is the technique used to determine the concentration of an unknown solution?

Solution

Titration is the technique used to determine the concentration of an unknown solution.

What is formed during a neutralization reaction?

Solution

A neutralization reaction forms salt and water.

Which solution resists change in pH when a small amount of acid or base is added?

Solution

A buffer solution resists change in pH when a small amount of acid or base is added.

What type of ions do acids produce in water according to Arrhenius theory?

Solution

According to the Arrhenius theory, acids are substances that increase the concentration of H⁺ ions in water.

According to the Arrhenius theory, a base is a substance that:

Solution

According to the Arrhenius theory, a base is a substance that increases the concentration of OH⁻ ions in water.

Which acid is used in the stomach to help break down food?

Solution

The stomach uses hydrochloric acid to help break down food.

Which one of the following is a salt?

Solution

KBr is a salt, formed from the neutralization reaction between an acid and a base.

Why is the Arrhenius theory limited in its explanation?

Solution

The Arrhenius theory is limited because it ignores the formation of hydronium ions (H₃O⁺) in water.

According to Bronsted-Lowry theory, a base is a substance that:

Solution

According to the Bronsted-Lowry theory, a base is a substance that accepts protons.

In the reaction: CH₃COOH + H₂O ⇌ CH₃COO⁻ + H₃O⁺, the conjugate base is:

Solution

In the reaction, CH₃COO⁻ is the conjugate base of CH₃COOH.

Which of the following statements best describes a Lewis acid?

Solution

A Lewis acid is described as an electron pair acceptor.

Which theory defines acids as proton donors and bases as proton acceptors?

Solution

The Bronsted-Lowry theory defines acids as proton donors and bases as proton acceptors.

What is the correct balanced neutralization reaction between NaOH and HCl?

Solution

The correct balanced neutralization reaction between NaOH and HCl is NaOH + HCl → NaCl + H₂O.

Which of the following is an application of calcium hydroxide?

Solution

Calcium hydroxide is used in the preparation of plaster of Paris.

What is the main limitation of Lewis theory?

Solution

The main limitation of Lewis theory is that it cannot explain the energy release during bond formation.

What does "pH" stand for?

Solution

"pH" stands for Potential of Hydrogen.

What is the formula for calculating pH?

Solution

The formula for calculating pH is \( \text{pH} = -\log[\text{H}^+] \).

What is the pH of a neutral solution at 25°C?

Solution

The pH of a neutral solution at 25°C is 7.

What is the value of the ionic product of water (Kw)?

Solution

The value of the ionic product of water (Kw) is \( 1 \times 10^{-14} \).

What does a pH of 3 indicate?

Solution

A pH of 3 indicates that the solution is strongly acidic.

If pH = 4, what is the pOH?

Solution

If pH = 4, then pOH = 14 - pH = 10.

What is the formula to calculate pOH?

Solution

The formula to calculate pOH is \( \text{pOH} = -\log[\text{OH}^-] \).

What is the pH of a 1 M HCl solution?

Solution

The pH of a 1 M HCl solution is 0, as it is a strong acid.

What is the relationship between pH and pOH at 25°C?

Solution

The relationship between pH and pOH at 25°C is \( \text{pH} + \text{pOH} = 14 \).

Which of the following has a pH greater than 7?

Solution

Blood has a pH greater than 7, making it slightly basic.

Which of the following is a weak electrolyte?

Solution

Pure water is a weak electrolyte because it dissociates slightly into ions.

What type of reaction typically forms a salt?

Solution

A neutralization reaction between an acid and a base typically forms a salt.

Which of the following is an example of a neutral salt?

Solution

NaCl is an example of a neutral salt.

Which of the following salts produces an acidic solution in water?

Solution

NH₄Cl produces an acidic solution in water.

Which salt is used in anti-acids to neutralize excess stomach acid?

Solution

Sodium hydrogen carbonate is used in anti-acids to neutralize excess stomach acid.

Which of the following is a basic salt?

Solution

CH₃COONa is a basic salt.

Which salt is used in X-ray imaging of the stomach?

Solution

Barium sulphate is used in X-ray imaging of the stomach.

What is the nature of salts like K₂CO₃ and Na₂CO₃ in water?

Solution

Salts like K₂CO₃ and Na₂CO₃ are basic in water.

Which compound pair forms an acidic buffer?

Solution

CH₃COOH and CH₃COONa form an acidic buffer.

What happens to the pH of a buffer solution when a small amount of acid is added?

Solution

When a small amount of acid is added to a buffer solution, the pH remains relatively stable.

What is a buffer solution made of?

Solution

A buffer solution is made of a weak acid or base and its conjugated salt.

Which property of buffer solution does NOT change significantly on adding water or acid?

Solution

The pH of a buffer solution does not change significantly on adding water or acid.