Question Discussion & Solution

1 atm is equal to 760 torr.

• The atmospheric pressure(atm) is unit of the pressure within the atmosphere of Earth. 
• At sea level the Earth's atmospheric pressure is 1 atm.
• The torr is an absolute-scale which is unit of pressure.
• The unit took its name from Evangelista Torricelli, an Italian physicist and mathematician who invented the barometer theory in 1644.

The correct answer is In 1829.

• In order to prevent the practice of Sati, in 1829 it was first banned under the "Bengal Sati Regulation".

Key Points

• The Bengal Sati Regulation
  • ​The Bengal Sati Regulation was passed on December 4, 1829, here is all you should definitely know about the practice of Sati.
  • The Bengal Sati Regulation which banned the Sati practice in all jurisdictions of British India was passed on December 4, 1829, by the then Governor-General Lord William Bentinck.

Additional Information

• About Sati practice
  • Sati was a historical Hindu practice, in which a widow sacrifices herself by sitting atop her deceased husband's funeral pyre.
  • The extent to which sati was practised in history is not known with clarity.
  • However, during the early modern Mughal period, it was notably associated with the elite Hindu Rajput clan.

The correct answer is A solid in gas.

Concept:

• A system made up of a substance distributed or scattered as minute particles of solid droplets of a liquid or extremely tiny bubbles of gas into the body of another substance is called a dispersion system.
• A dispersion system is a two-phase system.
• The distributed substance is called the dispersed phase and the continuous medium around it is called the dispersion medium.
• Depending upon the particle size of the dispersed phase, the dispersion system may be classified as 1. True solutions 2. Colloidal solutions 3. Suspensions.

Explanation:

Classification of colloids based on the type of phases:

• The colloidal system is heterogeneous in nature and consists of two phases called the dispersion medium and the dispersed phase.
• The component that is present in a small amount and behaves like a solute is called the dispersed phase and the component present in excess is called dispersion medium.
• Depending on the nature of dispersed phase and dispersion medium, colloids can be classified as:

• From the above table, it is clear that smoke contains solid particles suspended in the gaseous phase.
• Hence, smoke is a dispersion of solid in gas.

Important Points

• Gas in the gas phase is true solution. 

The correct answer is option 3 i.e. the Atomic Number

• The periodic table is based on Atomic Number.
• The atomic number is the number of protons found in the nucleus of every atom of that element. 
• The periodic table is managed by the International Union of Pure and Applied Chemistry, or IUPAC.
• In 1869, Dimitri Mendeleev included 63 known elements arranged according to increasing atomic weight. But there were many elements he could not place in the periodic table and with the discovery of new noble elements, there was a need to arrange the elements. Henry Moseley later arranged the elements in the periodic table by their number of protons rather than their atomic weights.
• The modern periodic table orders the elements according to increasing atomic number rather than increasing atomic weight.
• There are 118 elements in a periodic table. There are seven periods and eighteen groups in the modern periodic table.
• On moving from left to right in a period, the size of atoms(atomic size) decreases.
• On moving from left to right in a period, the metallic character of elements decreases, whereas the non-metallic character increases.
• While going down in a group of the periodic table, the size of atoms increases (or atomic size increases).
• While going down in a group of the periodic table, the metallic character of elements increases.
• Electronegativity and reactivity of non-metals increase along the period and decrease down the group.

The correct answer is option 3 i.e Backup.

Key Points

• Protecting data by copying it from the original source to a different destination is called Backup.
  • Backups can be used to recover data after its loss from data deletion or corruption.

Additional Information​ 

• The activity of creating sectors and tracks on a hard disk is called Formatting.
• The process of unauthorised access to information system is called Hacking.
  • One who does hacking is called Hacker.
  • Hackers are mainly classified as White Hat Hackers, Black Hat Hackers, Gray Hat Hackers.
• Data diddling is the unauthorised changing of data before or during their input to a computer system.