411. These days yellow lamps are frequently used as street light. Which one of the following us used in these lamps:
1. Sodium
2. Neon
3. Hydrogen
4. Nitrogen
Option “1” is correct. There are 2 types of street light bulbs are used by municipalities. They are sodium vapor and mercury vapor bulbs. The mercury vapor bulbs are usually a white ambient light and sodium on orange/yellow light.
412. In which of the following industries is mica used as a raw material-
1. Iron and steel
2. Toys
3. Glass and pottery
4. Electrical
Option “4” is correct. Mica is good conductor of heat and bad conductor of electricity so mica use in electrical industry.
Option “1” is correct. Nitrous Oxide (N2O) is also known as laughing gas. It is a colourless gas with a sweet odour and taste. It is also used as the anesthetic gas.
Option “1” is correct. Nila thotha is a compound of Copper and sulphate. Its chemical formula is CuSO4.5H2O.
415. Which is the fundamental element of all organic compounds?
1. Nitrogen
2. Oxygen
3. Carbon
4. Brimstone
Option “3” is correct. The organic compounds are a large class of chemical compounds in which one or more atoms of carbon are covalently linked atoms of other elements, most commonly Hydrogen, Oxygen or Nitrogen.
Option “4” is correct. Acetic acid is the chief component of vinegar. Vinegar is liquid consisting mainly of acetic acid (CH3COOH) and water.
417. To avoid ‘knocking’ of the engine of a car, which one of the following is used as an anti-knocking agent?
1. Ethyl alcohol
2. Butane
3. Lead Tetra Ethyl
4. White Petrol
Option “3” is correct. Tetraethyl Lead Pb is the chief antiknock agent for automotive gasoline or petrol.
418. Which of the following is not a part of an atom?
1. Electron
2. Proton
3. Neutron
4. Photon
Option “4” is correct. Proton, electron and neutron are part of an atom. These particles are also known as three fundamental particles, but the photon is associated with light energy and also known as energy packet of light.
419. What is the mass number of an element, the atom of which contains two protons, two neutrons and two electrons?
1. 2
2. 4
3. 6
4. 8
Option “2” is correct. The mass number of an element is the sum of a total number of protons and neutrons inside in its nucleus and represents by A. Therefore, mass number A = number of proton+number of neutron. Therefore, mass number = 2 + 2 = 4
420. Pasteurization is a process by which-
1. Milk is preserved at a very low temperature for 24 hours
2. Milk is heated for 8 hours
3. First milk is heated up to a longer time and then cooled suddenly within specified time
4. None of these
Option “3” is correct. In order to pasteurize milk, first, the milk is heated up to a longer time and then cooled suddenly within specified time. Pasteurization is a process invented the by French Scientist Louis Pasteur during the nineteenth century.
Q. 1. Ribosomes are made up of..
1. Protein and RNA
2. Protein and DNA
3. Carbohydrates
4. Cellulose
Q. 2. Electron transport chain occur at …
1. Protein fibre
2. Cellulose
3. mitochondrial inner membrane
4. Callose
banothshailu@123gemil.come
Which instrument is used to capture the purity of milk?
(A) hydrometer
(B). Isometric
(C). Lacto meter
Lactometer
I Love chemical…it’s my favourite subject..mere iss mein se hmesha hi boht ache marks aate hai….and my interest is also in chemistry…
Protein and RNA
Protein and RNA
vvvwvrww
Very good
Question bank chapter wise for class 12th CBSE 2025 board examination PCB