GK INFOPEDIA

[1] The metal used in storage batteries- A. Iron B. Copper C. Lead D. Zinc Ans: Lead Explanation : Commercially available batteries use a variety of metals and electrolytes. Anodes can be made of zinc, aluminum, lithium, cadmium, iron, metallic lead, lanthanide, or graphite [2] Type metal used in printing press is an alloy of […]

[1] When ice cubes are made, the entropy of water – A. does not change B. decreases C. increases D. may either increase or decrease depending on the process used Ans: decreases Explanation : When water is frozen into ice, the temperature drops below 0°C. Since the entropy of the solid is less than that […]

[1] Threshold limit value of copper in the atmospheric air is – A. 0.001 mg/m3 B. 0.01 mg/m3 C. 1.0 mg/m3 D. 5.0 mg/m3 Ans: 1.0 mg/m3 Explanation : Inspirable copper dust takes a predominantly fibrous effect. The ALV of copper aerosol in the workplace atmosphere is 0.5 mg/m3, while the threshold limit value (TLV) […]

[1] Who developed Hydrogen Bomb? A. Wernher Von Braun B. J. Robert Oppen Heimer C. Edward Teller D. Samuel Cohen Ans: Edward Teller Explanation : Portions of the development and history of the hydrogen bomb remain classified. But it is public knowledge that its chief architect was Dr. Edward Teller. The first H bomb (or […]

[1] Permanent – hardness of water may be removed by addition of – A. Alum B. Sodium carbonate C. Lime D. Potassium Permangante Ans: Sodium carbonate Explanation : Sodium carbonate (also known as washing soda or soda ash) is a sodium salt of carbonic acid. In domestic use, it is used as a water softener […]

[1] Taj Mahal is greatly affected due to – A. Tourists B. Acid rain C. Deforestation D. Sound pollution Ans: Acid rain Explanation : When sulphur pollutants fall on to buildings made from limestone and sandstone they react with minerals in the stone to form a powdery substance that can be washed away by rain. […]

[1] Diamond is the form of carbon that is – A. Crystalline B. Amorphous C. Chemical D. Alkaline Ans: Crystalline Explanation : Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. [2] Which of the following does not give benzoic acid on hydrolysis? A. […]

[1] The natural resource, known as black gold is – A. coal B. lead C. tin D. platinum Ans: coal Explanation : The term “coal is a black gold” is just a simple metaphor. Even today, we burn more coal than natural gas, more than nuclear, more than anything. [2] This group of alumino-silicate minerals […]

[1] Which of the following is biode-gradable? A. Paper B. D.D.T. C. Aluminium D. Plastic Ans: Paper Explanation : Paper is produced by pressing together moist fibers, typically cellulose pulp derived from wood, rags or grasses, and drying them into flexible sheets. [2] The ‘Green House effect’ is produced due to the presence of excess […]

[1] Which of the following is the lightest metal? A. Mercury B. Silver C. Lithium D. Lead Ans: Lithium Explanation : The lightest or least dense metal that is a pure element is lithium, which has a density of 0.534 g/cm3. This makes lithium nearly half as dense as water, so if lithium was not […]