Can any one explain the trends in modern periodic table of CH 5 in class 10 ncert science??? Please
Answers
HEY FOLLOWING ARE THE TRENDS IN MODERN PERIODIC TABLE
The atomic radius is the distance from the atomic nucleus to the outermost stable electron orbital in an atom that is at equilibrium. The atomic radius tends to decrease across a period from left to right due to the shrinking of the atom because of increasing nuclear force on the electrons. The atomic radius usually increases while going down a group due to the addition of a new energy level (shell which causes shrinkage in the size of the atoms across the period). However, atomic radii tend to increase diagonally, since the number of electrons has a larger effect than the sizeable nucleus. For example, lithium (145 picometer) has a smaller atomic radius than magnesium (150 picometer).
The ionization potential is the minimum amount of energy required to remove one electron from each atom in a mole of isolated,neutral and gaseous atom . The first ionization energy is the energy required to remove the first electron, and generally the nth ionization energy is the energy required to remove the atom's nth electron, after the (n−1) electrons before it has been removed. Trend-wise, ionization energy tends to increase while one progresses across a period because the greater number of protons (higher nuclear charge) attract the orbiting electrons more strongly, thereby increasing the energy required to remove one of the electrons. Ionization energy and ionization potentials are completely different. The potential is an intensive property and it is measured by "volt"; whereas the energy is an extensive property expressed by "eV" or "kJ/mole".
Electronegativity is a measure of the ability of an atom or molecule to attract pairs of electrons in the context of a chemical bond. The type of bond formed is largely determined by the difference in electronegativity between the atoms involved, using the Pauling scale. Trend-wise, as one moves from left to right across a period in the periodic table, the electronegativity increases due to the stronger attraction that the atoms obtain as the nuclear charge increases. Moving down in a group, the electronegativity decreases due to the longer distance between the nucleus and the valence electron shell, thereby decreasing the attraction, making the atom have less of an attraction for electrons or protons.
However, in the group 13 elements electronegativity increases from aluminium to thallium, and in group 14 electronegativity of lead is lower than that of tin.
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