Page 362 - General Knowledge

GENERAL KNOWLEDGE 2019

 In a microwave oven, the radiation causes water molecules in the cooking medium to vibrate
faster and thus raising its temperature.

 Ionizing radiations cause ionization of atoms and molecules of the medium through which
they pass.

IMPORTANT FACTS

 Mass – Body of matter with no definite shape. Unit is gram.
 Element – Matter is made of only one kind of atom.
 Compound – Combination of two or more kinds of elements.
 Molecules – Two or more atoms of the same element combine together.
 Types of mixture – Homogenous and Heterogeneous.
 Molecular formula for water is H 2O , Sulphuric acid is H 2SO 4
 Types of bonds – Covalent, Ionic and Hydrogen bonds.

 J.J. Thomson discovered electron in 1897 during investigation of cathode rays.
 Protons – Positive electrical charge. Each proton has 1 AMU.
 Neutron – No electrical charged and also called as neutral.
 John Dalton found Dalton‘s theory in 1808.
 Atomic number – Total number of nucleus of an atom. Represented by ‗Z‘
 Mass number – Number of protons and neutrons combined together. Represented by
‗A‘.
 Isotopes – Two or more atoms with same atomic number but different number of
neutrons.
 Ideal Gas Equation –
 Acid – Substance act as a proton donor. Base – Substance act as a proton acceptor.
 Galvanic Cell – Spontaneous reaction, current flows between electrodes.

 Electrolytic Cell – Non-spontaneous reaction. Consumes electrical energy.
 In the modern periodic law, table consists of 7 periods and 18 groups.
 Metallurgy – Extracting metal from ores.
 Air pollution – Presence of any solid, liquid or gaseous substance.
 Noise pollution – Unwanted sound.
 Soil pollution – Non-ionizing radiations constituted by electromagnetic waves.

358 | P a g e shop.ssbcrack.com