RRB Group D GK Questions 2026

The alkene series begins at two carbon atoms, so its first member is ethene, C2H4, and its second member is propene, C3H6.

C3H4 is propyne, and it fits the alkyne general formula CnH2n-2 when n equals 3. Alkynes are unsaturated hydrocarbons that carry at least one carbon-to-carbon triple bond, and the first member of the family is ethyne, C2H2, better known as acetylene and burnt with oxygen in welding torches.

Put n equal to 3 in the alkyne general formula CnH2n-2 and the result is C3H4, which is propyne, the second member of the alkyne series.

An alkene is an unsaturated hydrocarbon in which two carbon atoms are joined by a double bond, so the carbon-to-carbon double bond is its identity.

Alkanes are saturated hydrocarbons, so every bond between two carbon atoms is a single bond and all the remaining valencies are filled by hydrogen.

The d-block sits in the middle of the periodic table, bridging the s-block on the left and the p-block on the right.

The halogens are placed in Group 17 of the modern periodic table. This family has five members - fluorine, chlorine, bromine, iodine and astatine.

Earlier guidelines made annual renewal compulsory; the new framework sets validity by the recorded percentage of disability so that beneficiaries are spared repeated formalities.

The ministry announced the revision and stated that the new guidelines would come into force from that date, covering both the issuance and the renewal of exempted FASTags for eligible Divyangjan and persons with disabilities.

The revised framework of the Ministry of Road Transport and Highways ties the validity of an exempted FASTag to the percentage of disability on record, and the higher slab of 70 to 100 per cent carries a validity of five years.

That is where Paranur Toll Plaza stands, and it is the stretch on which Tamil Nadu received its first barrier-less tolling arrangement from the National Highways Authority of India.

Cameras at the plaza read the registration plate of every vehicle that crosses, and the FASTag-based Electronic Toll Collection system then debits the user fee from the account linked to that vehicle.

It lies on the Tambaram-Tindivanam section of NH-179B and has become the first location in Tamil Nadu where the National Highways Authority of India charges toll without a boom barrier, letting vehicles roll through while cameras and FASTag settle the fee.

An alkene carries one carbon-to-carbon double bond, and that bond uses up two hydrogen atoms that a saturated chain would have held, so the formula drops from CnH2n+2 to CnH2n. Putting n equal to 2 gives C2H4, ethene, the simplest alkene; n equal to 3 gives C3H6, propene.

Alkanes are saturated hydrocarbons in which carbon atoms are joined only by single bonds, and such a chain carries the largest possible number of hydrogen atoms, given by CnH2n+2.

Carbon is a non-metal, so it does not show metallic character; it neither loses electrons to form positive ions nor shows the lustre and malleability of metals.

An ionic compound is a lattice of positive and negative ions held by strong electrostatic attraction, and that force explains all its other properties.

A covalent bond is formed when two atoms share one or more pairs of electrons so that each completes its outermost shell.

A metal loses electrons and a non-metal gains them, so the transfer makes oppositely charged ions that attract each other, and that attraction is an ionic bond.

Sodium is a metal that gives up an electron easily and chlorine is a non-metal that accepts one, so the two form sodium chloride, an ionic compound.