Top 100 Most Expected Science Questions for Competitive Exams
Here are 100 one-liner Important and repeated questions are useful for all competitive Exams, along with their answers:
- What is the chemical formula of water?
Answer: H₂O - What is the SI unit of electric current?
Answer: Ampere - What is the atomic number of carbon?
Answer: 6 - Which acid is present in vinegar?
Answer: Acetic Acid - What is the process of converting solid into gas directly called?
Answer: Sublimation - Name the gas responsible for the greenhouse effect.
Answer: Carbon dioxide (CO₂) - What is the most reactive non-metal?
Answer: Fluorine - What is the main ore of aluminum?
Answer: Bauxite - What is the pH value of neutral substances?
Answer: 7 - Which element is used in making pencils?
Answer: Graphite - Which acid is secreted in the stomach?
Answer: Hydrochloric acid (HCl) - What is the name of the process in which energy is produced in cells?
Answer: Respiration - Name the enzyme that breaks down starch into sugar.
Answer: Amylase - What is the primary gas found in Earth’s atmosphere?
Answer: Nitrogen - What is the law of conservation of energy?
Answer: Energy cannot be created or destroyed, only transformed. - Which process turns milk into curd?
Answer: Fermentation - What is the main component of LPG (Liquefied Petroleum Gas)?
Answer: Butane and Propane - Which vitamin is known as ascorbic acid?
Answer: Vitamin C - What is the full form of DNA?
Answer: Deoxyribonucleic Acid - Which metal is used in making electrical wires?
Answer: Copper - What is the function of hemoglobin in the human body?
Answer: Transport oxygen - Name the organ that produces bile.
Answer: Liver - What is the chemical formula of common salt?
Answer: NaCl (Sodium chloride) - What is the unit of force?
Answer: Newton - What is the gas used in the process of photosynthesis?
Answer: Carbon dioxide (CO₂) - Which type of lens is used to correct myopia?
Answer: Concave lens - What is the human body’s primary source of energy?
Answer: Carbohydrates - Which vitamin is essential for blood clotting?
Answer: Vitamin K - What is the phenomenon of splitting of white light into its components called?
Answer: Dispersion - What is the SI unit of power?
Answer: Watt - Which gas is commonly used in fire extinguishers?
Answer: Carbon dioxide (CO₂) - What is the boiling point of water?
Answer: 100°C - Name the process by which plants make their food.
Answer: Photosynthesis - Which acid is present in lemon?
Answer: Citric acid - What is the basic unit of life?
Answer: Cell - Which process is used to separate oil from water?
Answer: Decantation - What is the most abundant gas in the universe?
Answer: Hydrogen - What is the function of chlorophyll in plants?
Answer: Absorb sunlight for photosynthesis - What is the chemical symbol for iron?
Answer: Fe - What is the formula of methane?
Answer: CH₄ - What is the byproduct of photosynthesis?
Answer: Oxygen (O₂) - Which non-metal is a good conductor of electricity?
Answer: Graphite - What is the main constituent of biogas?
Answer: Methane (CH₄) - What is the chemical name of baking soda?
Answer: Sodium bicarbonate (NaHCO₃) - Which organ filters waste from the blood?
Answer: Kidneys - What is the atomic number of hydrogen?
Answer: 1 - Name the hardest natural substance.
Answer: Diamond - Which type of reproduction involves only one parent?
Answer: Asexual reproduction - Which part of the plant conducts water?
Answer: Xylem - What is the SI unit of temperature?
Answer: Kelvin - What is the main function of the heart?
Answer: Pump blood - What is the chemical formula for rust?
Answer: Fe₂O₃·nH₂O (Iron oxide) - What is the common name of sodium chloride?
Answer: Table salt - Which vitamin helps in the absorption of calcium?
Answer: Vitamin D - What is the formula for glucose?
Answer: C₆H₁₂O₆ - What is the mode of nutrition in fungi?
Answer: Saprotrophic - What is the law that states that current is directly proportional to voltage?
Answer: Ohm’s Law - Which organ of the body is affected by pneumonia?
Answer: Lungs - What is the chemical formula of ozone?
Answer: O₃ - Name the process of water cycle in nature.
Answer: Evaporation, condensation, and precipitation - Which part of the cell contains genetic material?
Answer: Nucleus - What is the SI unit of frequency?
Answer: Hertz (Hz) - What is the liquid part of blood called?
Answer: Plasma - Which gas is evolved during respiration?
Answer: Carbon dioxide (CO₂) - Which planet is known as the Red Planet?
Answer: Mars - What is the chemical symbol for gold?
Answer: Au - What is the function of ribosomes in a cell?
Answer: Protein synthesis - Which organism is responsible for malaria?
Answer: Plasmodium - What is the atomic number of oxygen?
Answer: 8 - Name the metal present in chlorophyll.
Answer: Magnesium - What is the effect of electric current on a magnetic needle?
Answer: It gets deflected. - What is the role of stomata in plants?
Answer: Gas exchange - What is the SI unit of work?
Answer: Joule - What is the smallest bone in the human body?
Answer: Stapes - What is the outermost layer of the Earth called?
Answer: Crust - Which disease is caused by a deficiency of insulin?
Answer: Diabetes - Which part of the brain controls balance and coordination?
Answer: Cerebellum - What is the process of turning liquid into vapor called?
Answer: Evaporation - Which chemical is used for purifying water?
Answer: Chlorine - What is the speed of light in a vacuum?
Answer: 3 x 10⁸ m/s - What is the full form of ATP?
Answer: Adenosine Triphosphate - Which acid is present in the human stomach?
Answer: Hydrochloric acid (HCl) - Which element is the most abundant in the Earth’s crust?
Answer: Oxygen - Which organ is responsible for detoxification in the human body?
Answer: Liver - What is the main gas present in LPG?
Answer: Butane - What is the chemical formula for ammonia?
Answer: NH₃ - Which vitamin is necessary for vision?
Answer: Vitamin A - What is the main constituent of biogas?
Answer: Methane (CH₄) - What is the main cause of acid rain?
Answer: Sulfur dioxide (SO₂) and nitrogen oxides (NOx) - What is the charge of an electron?
Answer: Negative - What is the phenomenon where a liquid changes into solid called?
Answer: Freezing - What is the outermost layer of the human skin?
Answer: Epidermis - Which gas is released during combustion?
Answer: Carbon dioxide (CO₂) - Which type of cell division occurs in body cells?
Answer: Mitosis - What is the primary pigment in human blood?
Answer: Hemoglobin - Which instrument is used to measure electric current?
Answer: Ammeter - What is the main function of white blood cells?
Answer: Fight infections - Which metal is used to make the filament of an electric bulb?
Answer: Tungsten - What is the freezing point of water?
Answer: 0°C - Which disease is caused by the deficiency of Vitamin C?
Answer: Scurvy
