Option “C” is correct The chemical formula of Sodium Benzoate is NaC7HsO2 It is widely used as food preservative.
342. Which one of the following gases, released from biogas plant is used as a fuel gas?
1. Butane
2. Propane
3. Methane
4. Ethane
Option “C” is correct Methane is the principal gas in biogas. It is also the main component of natural gas, a fossil fuel, can be used to replace natural gas in many applications including cooking, heating, steam production, etc.
343. Which of the following is an antidiabatic drug?
Option “A” is correct Insulin is an anti-diabatic drug.
344. Which of the following pairs is INCORRECT?
I. Hematite: Iron
II. Pitchblende: Copper
III. Monazite: Thorium1. Only I
2. Only II
3. Only I and II
4. Only I and III
Option “B” is correct Pitchblende is a radioactive, uranium-rich mineral and ore. It has a chemical composition that is largely UO2, but also contains UO3 and oxides of lead, thorium, and rare earth elements. It is known as pitch blende due to its black color and high density.
345. What is an endothermic reaction?
1. Reaction in which heat is released.
2. Reaction in which heat is absorbed.
3. Reaction in which neither heat is released nor absorbed.
4. None of these
Option “B” is correct The term endothermic process describes a process or reaction in which the system absorbs energy in the form of heat.
346. The depletion in Ozone layer is caused by ___________.
Option “C” is correct The ozone layer is a region of Earth’s stratosphere that absorbs most of the Sun’s ultraviolet (UV) radiation. The depletion in Ozone layer is caused by Chlorofluorocarbons.
347. When water itself combines chemically with some element or mineral it is called –
Option “C” is correct When water itself combines chemically with some element or mineral called hydration.
348. Rodenticide is the chemical which is used to control.
1. Bats
2. Monkeys
3. Mouse
4. Rabbits
Option “C” is correct} Potassium Cyanide (KCN) or Zinc Phosphide is a highly toxic chemical used as a rodenticide – a poison to kill the mouse.
349. Which of the following is a non-metal that remains liquid at room temperature?
1. Phosphorous
2. Bromine
3. Chlorine
4. Helium
Option “B” is correct Bromine is the only non-metal and Mercury only metal, liquid at room temperature.
350. Which one of the following liquids is very good conductor of heat?
1. Mercury
2. Benzene
3. Ether
4. None of these
Option “A” is correct Mercury is a chemical element with the symbol (Hg). Mercury is used in thermometers due to its special properties. Mercury is good conductor of heat.
