Acids & Bases — Set 1
Chemistry · अम्ल और क्षार · Questions 1–10 of 60
What is the pH value of a neutral aqueous solution at 25°C?
Correct Answer: A. 7
• **7** = A pH of 7 represents a neutral solution where hydrogen and hydroxyl ions are equal. • (Contextual detail from explanation) • 💡 Wrong-option analysis: B: 1; C: 0; D: 14
Which acid is predominantly found in lemons and oranges?
Correct Answer: A. Citric acid
• **Citric acid** = Citric acid is the primary organic acid found in citrus fruits like lemons. • (Contextual detail from explanation) • 💡 Wrong-option analysis: B: Oxalic acid; C: Acetic acid; D: Tartaric acid
What color does blue litmus paper turn when dipped in an acidic solution?
Correct Answer: B. Red
• **Red** = Acids turn blue litmus paper red due to the chemical reaction with hydrogen ions. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Yellow; C: Green; D: Colorless
Which of the following is commonly known as 'Milk of Magnesia'?
Correct Answer: C. Magnesium hydroxide
• **Magnesium hydroxide** = Magnesium hydroxide is called Milk of Magnesia because of its milk-like appearance when suspended in water. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Sodium hydroxide; B: Calcium hydroxide; D: Ammonium hydroxide
Which gas is evolved when a dilute acid reacts with a metal like zinc?
Correct Answer: D. Hydrogen
• **Hydrogen** = Hydrogen gas is produced when metals react with acids through a displacement reaction. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Carbon dioxide; B: Oxygen; C: Nitrogen
What is the chemical name of Vinegar?
Correct Answer: D. Acetic acid
• **Acetic acid** = Acetic acid is the main component of vinegar, usually present in a 5-8% concentration. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Citric acid; B: Nitric acid; C: Methanoic acid
Which of the following bases is highly soluble in water and termed an 'Alkali'?
Correct Answer: C. Sodium hydroxide
• **Sodium hydroxide** = Sodium hydroxide is an alkali because it dissolves completely in water to release hydroxide ions. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Aluminum hydroxide; B: Copper hydroxide; D: Ferric hydroxide
Which acid is present in the sting of an ant?
Correct Answer: A. Formic acid
• **Formic acid** = Formic acid, also known as methanoic acid, is injected into the skin during an ant bite. • (Contextual detail from explanation) • 💡 Wrong-option analysis: B: Lactic acid; C: Malic acid; D: Stearic acid
What is the pH of a solution that turns phenolphthalein indicator pink?
Correct Answer: B. More than 7
• **More than 7** = The correct answer is 'More than 7'. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Exactly 0; C: Less than 7; D: Exactly 7
Which of the following is a strong mineral acid?
Correct Answer: D. Sulfuric acid
• **Sulfuric acid** = Sulfuric acid is a strong mineral acid that ionizes completely in aqueous solutions. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Oxalic acid; B: Tartaric acid; C: Carbonic acid