Railway GK Questions 2026

Fertility needs mineral nutrients such as nitrogen, phosphorus and potassium from the weathered rock, and organic matter, that is humus from decayed plants and animals, which holds water, feeds soil organisms and releases nutrients slowly.

Weathering is the natural breaking down of rock by temperature, water, wind and living things, and it is the process that makes soil in the first place; it is not a technique that a farmer applies to save soil, so it cannot be a conservation method.

In sheet erosion water spreads over a wide slope and carries away a thin, even film of topsoil, so nothing obvious is left behind to see, and the loss is noticed only years later as falling yields.

What it is rich in is calcium carbonate, magnesium, potash and lime, and remembering that short list is the safest way to answer any statement question on this soil.

A delta is built out of silt that a river carries down and drops where it meets the sea, so deltaic land is alluvial by definition, and the eastern coastal deltas of the Mahanadi, Godavari, Krishna and Kaveri are among the most fertile rice tracts of the country.

It is a molecule of sixty carbon atoms arranged in a closed cage of pentagons and hexagons, exactly like the panels of a football, and it is named after the architect who designed domes of the same geometry.

Ethanoic acid, better known as acetic acid and familiar as vinegar in dilute form, has the formula CH3COOH, and the -COOH group at the end is what makes it acidic, since it releases a hydrogen ion in water and turns blue litmus red.

Vegetable oils contain unsaturated chains with carbon to carbon double bonds; hydrogen adds across those double bonds in the presence of nickel or palladium, turning them into single bonds, so the oil becomes saturated and sets into a solid fat.

Going from methane to ethane, or from ethanol to propanol, adds one carbon atom of mass twelve and two hydrogen atoms of mass one each, which is fourteen in all, and it is this fixed step that defines a homologous series.

In graphite every carbon atom is bonded to only three others within a layer, so the fourth valence electron of each atom is free to move along the layer, and moving electrons constitute an electric current.

Catenation is the self-linking of atoms of the same element, and carbon shows it more strongly than any other element because the carbon to carbon bond is short and exceptionally strong, which is why chains of many carbon atoms remain stable.

When enough air reaches the burner, every carbon atom of the fuel is oxidised fully to carbon dioxide and the flame is blue and hot, giving the maximum heat for the gas consumed.

An alkyne contains a carbon to carbon triple bond, which needs at least two carbon atoms, so the series begins with ethyne, C2H2, also called acetylene and used with oxygen in welding.

The prefix di stands for two and the ending ene for a carbon to carbon double bond, so a diene is a hydrocarbon carrying exactly two such bonds; buta-1,3-diene, the raw material of synthetic rubber, is the standard example.

Hexane, C6H14, can be drawn as a straight chain of six carbons, as two chains of five carbons with a methyl branch in different positions, and as two chains of four carbons carrying branches, which gives five different structures with the same molecular formula.

Liquefied petroleum gas is a mixture of these two saturated hydrocarbons, which are gases at ordinary pressure but turn liquid under moderate pressure, so a large quantity of fuel fits into a small cylinder; a strong-smelling compound is added so that a leak is noticed.

It grew out of a department for non-conventional energy sources created in 1982, became a full ministry in 1992 and took its present name in 2006, and India is among the very few countries in the world to have a separate ministry devoted to this sector.

Projects of this size and below fall under the small hydro programme of the Ministry of New and Renewable Energy, while larger schemes are handled as conventional hydro power by the Ministry of Power.

The plan set out eight missions covering solar energy, enhanced energy efficiency, sustainable habitat, water, the Himalayan ecosystem, a green India, sustainable agriculture and strategic knowledge for climate change, and every later programme in this field refers back to it.

Both are long, narrowing inlets on the coast of Gujarat, and such a shape funnels the incoming tide so that the difference between high and low water is large, which is exactly what a tidal power scheme needs; the Sundarbans coast is the other site usually named.