Determine which of the following trends will be observed down the same group in the periodic table. Ionic radius decreasesAtomic radius increasesFirst ionisation energy increases Electronegativity increases

To determine the trend down the same group in the periodic table, we need to analyze the given properties: ionic radius, atomic radius, first ionization energy, and electronegativity.

1. Ionic radius: The trend down the same group is that the ionic radius increases. This is because as we move down the group, additional electron shells are added, increasing the size of the atom and its corresponding ions.

2. Atomic radius: Similarly, the atomic radius also increases down the same group. This is due to the addition of electron shells, which leads to an increase in the size of the atom.

3. First ionization energy: In contrast to the previous two trends, the first ionization energy increases down the same group. This means that it becomes more difficult to remove the outermost electron as we move down the group. This is because the outermost electron is held more tightly by the increasing positive charge of the nucleus.

4. Electronegativity: Lastly, electronegativity also increases down the same group. Electronegativity is the tendency of an atom to attract electrons towards itself in a chemical bond. As we move down the group, the atomic size increases, resulting in a weaker attraction for electrons and thus higher electronegativity.

In summary, the observed trends down the same group in the periodic table are: ionic radius and atomic radius increase, while first ionization energy and electronegativity increase.