Q. Chlorofluorocarbons are replacing with less harmful compounds such as

View solution

Q. Chlorofluorocarbons are primarily used as

View solution

Q. The names of the scientists, Newlands, Mendeleev, and Meyer are associated with the development of

View solution

Q. The molecular formula of phosphorous is

View solution

Q. The inert gases are ____ in water

View solution

Q. The method of concentrating the ore which makes use of the difference in density between ore and impurities is called

View solution

Q. The metal that is usually extracted from sea water is

View solution

Q. The formula C6H5-CO-CH3 represents

View solution

Q. The maximum number of covalent formed by nitrogen is

View solution

Q. The mass number of an atom is equal to

View solution

Q. Equal masses of oxygen, hydrogen and methane are kept under identical conditions. The ratio of the volumes of gases will be

View solution

Q. The National Chemical Laboratory is situated in

View solution

Q. The number of atoms present in 21.6 gram of silver (atomic weight = 108) are same as the molecules in

View solution

Q. The number of waves made by an electron moving in an orbit having maximum magnetic quantum number is +3

View solution

Q. The half life period of an isotope is 2 hours. After 6 hours what fraction of the initial quantity of the isotope will be left behind?

View solution

Q. The isomerism which exists between CH3CHCI2 and CH2CI. CH2CI is

View solution

Q. The human body is made up of several chemical elements; the element present in the highest proportion (65%) in the body is

View solution

Q. The hottest part of the gas flame is known as

View solution

Q. The number of electrons presents in H+ is

View solution

Q. The organic reaction represented by equation CH3 - CH = O + H2NOH gives CH3 - CH - NH + H2O is an example of

View solution