Acids & Bases — Set 2
Chemistry · अम्ल और क्षार · Questions 11–20 of 60
What happens during a neutralization reaction?
Correct Answer: A. An acid and a base form salt and water
• **An acid and a base form salt and water** = In neutralization, the H+ ions of an acid react with OH- ions of a base to form water and a salt. • (Contextual detail from explanation) • 💡 Wrong-option analysis: B: A base turns blue litmus red; C: A metal and acid form gas; D: An acid becomes more concentrated
Which base is used in the manufacturing of soap?
Correct Answer: D. Sodium hydroxide
• **Sodium hydroxide** = Sodium hydroxide, also known as caustic soda, is used in the saponification process to make soap. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Calcium hydroxide; B: Ammonium hydroxide; C: Magnesium hydroxide
Which acid is produced in the human stomach to help in digestion?
Correct Answer: D. Hydrochloric acid
• **Hydrochloric acid** = Hydrochloric acid is secreted by the gastric glands to create an acidic environment for enzymes. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Sulfuric acid; B: Phosphoric acid; C: Nitric acid
What is the common name for Calcium Hydroxide?
Correct Answer: A. Slaked lime
• **Slaked lime** = Calcium hydroxide is commonly known as slaked lime and is produced by adding water to quicklime. • (Contextual detail from explanation) • 💡 Wrong-option analysis: B: Caustic soda; C: Quick lime; D: Baking soda
Which indicator is prepared from a common kitchen spice and turns reddish-brown in bases?
Correct Answer: D. Turmeric
• **Turmeric** = Turmeric is a natural indicator that stays yellow in acidic solutions but turns reddish-brown in basic ones. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Clove; B: Vanilla; C: Onion
Which of the following substances has a pH value greater than 10?
Correct Answer: C. Sodium hydroxide solution
• **Sodium hydroxide solution** = Sodium hydroxide is a strong base, and its concentrated solutions have a pH close to 14. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Lemon juice; B: Milk; D: Blood
According to the Arrhenius theory, what do acids produce in water?
Correct Answer: A. Hydrogen ions
• **Hydrogen ions** = Arrhenius defined acids as substances that increase the concentration of H+ ions when dissolved in water. • (Contextual detail from explanation) • 💡 Wrong-option analysis: B: Hydroxide ions; C: Chloride ions; D: Sodium ions
Which acid is found in tamarind and grapes?
Correct Answer: C. Tartaric acid
• **Tartaric acid** = Tartaric acid is a white crystalline organic acid occurring naturally in many fruits like grapes and tamarind. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Acetic acid; B: Malic acid; D: Lactic acid
What is the nature of metal oxides generally?
Correct Answer: B. Basic
• **Basic** = Most metal oxides are basic in nature and react with water to form bases or with acids to form salts. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Amphoteric only; C: Acidic; D: Neutral
Which of the following is an olfactory indicator?
Correct Answer: A. Onion
• **Onion** = Onion is an olfactory indicator because its characteristic smell changes when it is mixed with a base. • (Contextual detail from explanation) • 💡 Wrong-option analysis: B: Phenolphthalein; C: Litmus; D: Methyl orange