721. The study of heavenly bodies is known as astronomy.
722. The main culprit of the greenhouse effect is carbon dioxide, but the second element contributing most is methane.
723. When a single month has two full moons, the second moon is called a blue moon.
724. Echo is a result of sound reflection.
725. The adult human brain is about 2% of the total body weight.
726. The average length of the kidney of a man is about 10cm to 13cm.
727. The element used in pencils is graphite.
728. Columns in the Periodic table are called groups.
729. Tocopherol is the chemical name of Vitamin E.
730. The world’s warmest sea is the Red Sea.
731. The major component of honey is fructose.
732. In blood, the percentage of water is approximately 90%.
733. The major part of natural gas, petroleum, and coal consists of carbon.
734. One gram of carbohydrates gives an energy amount of 4.1 K Calories.
735. The alloy of aluminum used for making magnets is Alnico.
736. Which one of the following gases is readily soluble in water at room temperature? Ammonia.
737. Air contains the maximum amount of nitrogen.
738. Silver melts at a temperature of 961.8°C.
739. Lactometer is used for testing milk.
740. The planet of the Solar system which has the maximum number of moons is Jupiter.