Chapter 20: Acids, Bases and Salts – Important MCQs
- Which of the following is a natural indicator?
A. Phenolphthalein
B. Methyl orange
C. Red cabbage juice
D. Universal indicator
✔️ Answer: C. Red cabbage juice - Which gas is released when acids react with metals?
A. Carbon dioxide
B. Oxygen
C. Hydrogen
D. Nitrogen
✔️ Answer: C. Hydrogen - Which acid is found in vinegar?
A. Citric acid
B. Acetic acid
C. Oxalic acid
D. Tartaric acid
✔️ Answer: B. Acetic acid - The pH value of neutral solution is:
A. 14
B. 0
C. 7
D. 5
✔️ Answer: C. 7 - An antacid used to treat indigestion is:
A. Sodium chloride
B. Sodium carbonate
C. Sodium hydroxide
D. Sodium hydrogen carbonate
✔️ Answer: D. Sodium hydrogen carbonate - Which of the following salts is basic in nature?
A. Sodium chloride
B. Ammonium chloride
C. Sodium carbonate
D. Potassium nitrate
✔️ Answer: C. Sodium carbonate - What is formed when an acid reacts with a base?
A. Acid only
B. Salt and water
C. Base only
D. Gas and base
✔️ Answer: B. Salt and water - When red litmus paper is dipped in a basic solution, it turns:
A. Red
B. Blue
C. Green
D. Yellow
✔️ Answer: B. Blue - Which of the following is not a property of bases?
A. Bitter taste
B. Soapy touch
C. Turns red litmus blue
D. Turns blue litmus red
✔️ Answer: D. Turns blue litmus red - Which of the following shows acidic nature in water only?
A. NaCl
B. HCl gas
C. Glucose
D. Alcohol
✔️ Answer: B. HCl gas
Chapter 21: Heat and Temperature – Important MCQs
- The SI unit of heat is:
A. Degree Celsius
B. Calorie
C. Fahrenheit
D. Joule
✔️ Answer: D. Joule - Which instrument is used to measure temperature?
A. Barometer
B. Thermometer
C. Ammeter
D. Voltmeter
✔️ Answer: B. Thermometer - Which of the following is the correct unit of temperature in the SI system?
A. Celsius
B. Fahrenheit
C. Kelvin
D. Joule
✔️ Answer: C. Kelvin - Heat flows from:
A. Cold object to hot object
B. Hot object to cold object
C. Both directions equally
D. None of these
✔️ Answer: B. Hot object to cold object - The boiling point of water on the Celsius scale is:
A. 0°C
B. 50°C
C. 100°C
D. 212°C
✔️ Answer: C. 100°C - Which property of a liquid is used in a thermometer to measure temperature?
A. Pressure
B. Volume expansion
C. Density
D. Color
✔️ Answer: B. Volume expansion - Which of the following is not a mode of heat transfer?
A. Conduction
B. Convection
C. Radiation
D. Emission
✔️ Answer: D. Emission - The process of heat transfer in solids is called:
A. Radiation
B. Convection
C. Conduction
D. Transmission
✔️ Answer: C. Conduction - What is the normal human body temperature in Fahrenheit?
A. 98.6°F
B. 100°F
C. 37°F
D. 80°F
✔️ Answer: A. 98.6°F - The temperature at which ice melts is:
A. 100°C
B. 0°C
C. 273 K
D. Both B and C
✔️ Answer: D. Both B and C
