(i) Yes, elements belong to the same group but are not from the same period. (ii) We know that m.p. decreases on down the group. Hence, from the above table, the elements can be ordered according to their period as follows: Elements B C A m.p. 180.0 97.0 63.0 The metallic character increases as one moves down the group. Hence, the order of the given elements with increasing metallic character is as follows: B Intext 3 The energy required to remove the residual electrons one by one is called successive ionization energy. (a) Ionization energy increases as we move from left to right across a period as the atomic size decreases. (b) Ionization energy decreases down a group as the atomic size increases. Helium has the highest ionization energy of all the elements cesium has the lowest ionization energy. Second period: Neon > Fluorine > Oxygen > Nitrogen > Carbon > > Beryllium > Lithium Third Period: Argon> Chlorine > Sulphur > Phosphorus > Silicon > Aluminum >Magnesium > Sodium (a) Electron affinity is the energy released when a neutral gaseous atom acquires an electron to form an anion. (b) Second period: Lithium<Boron<Carbon<Oxygen<Fluorine Neon, Nitrogen and Beryllium do not follow the trend. Electron affinity depends on:
(i) Yes, elements belong to the same group but are not from the same period. (ii) We know that m.p. decreases on down the group. Hence, from the above table, the elements can be ordered according to their period as follows: Elements B C A m.p. 180.0 97.0 63.0 The metallic character increases as one moves down the group. Hence, the order of the given elements with increasing metallic character is as follows: B Intext 3 The energy required to remove the residual electrons one by one is called successive ionization energy. (a) Ionization energy increases as we move from left to right across a period as the atomic size decreases. (b) Ionization energy decreases down a group as the atomic size increases. Helium has the highest ionization energy of all the elements cesium has the lowest ionization energy. Second period: Neon > Fluorine > Oxygen > Nitrogen > Carbon > > Beryllium > Lithium Third Period: Argon> Chlorine > Sulphur > Phosphorus > Silicon > Aluminum >Magnesium > Sodium (a) Electron affinity is the energy released when a neutral gaseous atom acquires an electron to form an anion. (b) Second period: Lithium<Boron<Carbon<Oxygen<Fluorine Neon, Nitrogen and Beryllium do not follow the trend. Electron affinity depends on:
CH-1-Periodic-Table.docx