Correct Answer :   Technetium

Technetium. The first element that was synthesised, rather than being discovered in nature, was technetium in 1937. This discovery filled a gap in the periodic table, and the fact that no stable isotopes of technetium exist explains its natural absence on Earth (and the gap).

Correct Answer :   Light energy into electrical energy

Correct Answer :   8.5

Correct Answer :   Mercury

Correct Answer :   Cinnabar

Correct Answer :   Methane

CNG is the compressed form of Natural Gas, which is mainly composed of methane [CHâ‚„]), which is less than 1% of the volume it occupies at standard atmospheric pressure so that large volume of gas can be stored in CNG cylinder.

Correct Answer :   Earthworm

Earthworms are called as nature's ploughman because they loosen the soil when they burrow and this is good for the soil because it lets the CO2 out and the O2 in. It also helps to mix the nutrients in the soil, making it better for plants to grow.

Correct Answer :   Surface tension

The principle behind the working of a ball pen is surface tension and gravity. The ink gets spread over the ball due to surface tension. The flow of ink to the ball is based on the surface tension. If the surface tension is high, the ink won't spread over the ball properly.

Correct Answer :   Knot

Nautical miles are used for charting and navigating. A knot is one nautical mile per hour (1 knot = 1.15 miles per hour ).

Correct Answer :   O. Schmid

O Schmidt suggests the earth's origin is from gases and dust particles.