Define what electronegativity is and explain the pattern on the table as you move to the right across it.

Electronegativity is defined as the tendency of element to attract the bond pair electrons towards itself in a covalent bond. On aPauling scale Fluorine has been given a highest electronegativity of 4.

Trends in Periodic Table:

                Along the Period:
                                           Moving from left to right along the period in periodic table that electronegativity increases. This is because the number of protons along the period increases while the number of shell remains constant. Hence, more protons attracts electrons more towards themselves.

                Along the Group:
                                           Moving from top to bottom electronegativity decreases due to increase in number of shells. This is because the shielding effect increases and nucleus has less effect on electrons, therefore less attracted.

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