Option “2” is correct. A redox reaction is a type of chemical reaction that involves both oxidation and reduction simultaneously.
436. Who discovered Nitrogen?
1. Faraday
2. Heisenberg
3. Hooke
4. Rutherford
Option “4” is correct. Nitrogen is a chemical element with symbol N and atomic number 7. It was first discovered and isolated by Scottish physician Daniel Rutherford in 1772.
437. Device used for the detection and measurement of all types of radiation (alpha, beta and gamma)-
Option “1” is correct. A Geiger counter (Geiger-Muller tube) is a device used for the detection and measurement of all types of radiation alpha, beta and gamma radiation.
438. Carnotite is an ore/mineral of _________.
1. Beryllium
2. Chromium
3. Uranium
4. Copper
Option “3” is correct. Carnotite an important uranium ore.
439. There is a protocol signed to reduce production of CFC, known as –
1. CFC Protocol
2. IR Protocol
3. Montreal Protocol
4. UV Protocol
Option “3” is correct. The Montreal Protocol is an international environmental agreement with universal ratification to protect the earth’s ozone layer by eliminating use of ozone depleting substances (ODS) like CFC, which would otherwise allow increased UV radiation to reach the earth.
440. Malachite is an ore/mineral of –
1. Lead
2. Manganese
3. Mercury
4. Copper
Option “4” is correct. Malachite is an ore/mineral of copper.
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