Chemistry ERT - ITEM 3
Item 3.1 and 3.2 – Graphs
The trend for the number of electrons in the valence shell for an element is clearly seen in this graph. The lowest point of each peak coincides with the Group I alkali metals. From there on, the electron count climbs until a full shell is reached at eight electrons, i.e. the noble gases who have full outer shells. The full shell signals the end of a Period at Group VIII, and then it begins again in Group I in a new Period. There is an anomaly from Scandium (Sc) to Zinc (Zn) where the electron count doesn’t rise, it hovers around 1-2 electrons in the valence shell; these metals are the transition elements (metals). Transition metals are different as they can be found in different oxidation states, that is, different ionic states e.g. Iron (Fe) has two oxidation states, Fe (I) and Fe (II). This means that Iron can have the ionic form of Fe+2 or Fe+3.
There is a density trend on the Periodic Table, but …show more content…
This is due to the fact that Atomic Radius increases from top to bottom in a Group, but decreases from left to right in a Period. Why? This is because at the beginning of a new Period (Group I), a new electron shell is added as the previous one was filled. This new shell increases the atomic radius of the element. But as you move across the Period, the number of protons and electrons in the atom increase. These protons and electrons have a greater nuclear attraction, as the positive protons and negative electrons are drawn towards each other, bunching the electron shells closer together than they were before. This is why Atomic Radius decreases as you move across the Period; more protons = more electrons = more nuclear attraction = more closely bound shells = smaller atomic
Item 3.1 and 3.2 – Graphs
The trend for the number of electrons in the valence shell for an element is clearly seen in this graph. The lowest point of each peak coincides with the Group I alkali metals. From there on, the electron count climbs until a full shell is reached at eight electrons, i.e. the noble gases who have full outer shells. The full shell signals the end of a Period at Group VIII, and then it begins again in Group I in a new Period. There is an anomaly from Scandium (Sc) to Zinc (Zn) where the electron count doesn’t rise, it hovers around 1-2 electrons in the valence shell; these metals are the transition elements (metals). Transition metals are different as they can be found in different oxidation states, that is, different ionic states e.g. Iron (Fe) has two oxidation states, Fe (I) and Fe (II). This means that Iron can have the ionic form of Fe+2 or Fe+3.
There is a density trend on the Periodic Table, but …show more content…
This is due to the fact that Atomic Radius increases from top to bottom in a Group, but decreases from left to right in a Period. Why? This is because at the beginning of a new Period (Group I), a new electron shell is added as the previous one was filled. This new shell increases the atomic radius of the element. But as you move across the Period, the number of protons and electrons in the atom increase. These protons and electrons have a greater nuclear attraction, as the positive protons and negative electrons are drawn towards each other, bunching the electron shells closer together than they were before. This is why Atomic Radius decreases as you move across the Period; more protons = more electrons = more nuclear attraction = more closely bound shells = smaller atomic