General Science Online Quiz Test

Hydrogen is lighter than air. When a balloon is filled with hydrogen gas the weight of the balloon is less than the weight of air displaced by the balloon.

Asteroids are rocky objects revolving around the sun that are too small to be called planets. The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Mars and Jupiter.

Electron microscopes are used to investigate the ultrastructure of a wide range of biological and inorganic specimens including microorganisms, cells, large molecules, structure of bacteria and viruses, etc.

The carbon dating method (carbon-14 dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon. The carbon dating method is not used to determine the age of rock as it only works for objects that are younger than about 50,000 years, and most rocks of interest are older than that.

Rainwater is considered the purest form of water available on the Earth. However, the rainwater we receive on earth is not necessarily pure, as it brings down impurities and particles present in the atmosphere along with it. Distilled water is a type of purified water that has had both contaminants and minerals removed.

Anthracite is the highest grade and best equality coal. It is a hard, very low content of volatile compact variety of coal that has a high luster. It has the highest carbon content (92.1% to 98%), the fewest impurities, and the highest calorific content.

Hepatitis is a viral disease caused by hepatitis viruses A, B, C, D, and E. It infects liver cells and causes inflammation.

Estrogen is a female hormone that plays various roles. It helps develop and maintain both the reproductive system and female characteristics, such as breasts and pubic hair.

Broad-spectrum antibiotics are active against a wider number of bacterial types. Narrow-spectrum antibiotics are active against a select group of bacterial types. Streptomycetes produce over two-thirds of the clinically useful antibiotics of natural origin.

Loris, Alligator and Cow have teeth. Peacock, Ostrich, Tortoise, Owl, Crow and Kiwi do not have teeth. Birds do not have teeth, although they may have ridges on their bills that help them grip food. Turtles and tortoises don't have teeth. Instead, their mouths have a hard, sharpened edge that they use to bite with, kind of like a bird's beak.