Calculating these energies exactly is not possible except for the simplest systems i. Therefore, approximation methods are routinely employed, with different methods varying in complexity computational time and in accuracy compared to empirical data.
Ionization Energies increase going left to right across a period and increase going up a group. As you go up a group, the ionization energy increases, because there are less electron shielding the outer electrons from the pull of the nucleus. Therefore, it requires more energy to out power the nucleus and remove an electron.
As we move across the periodic table from left to right, the ionization energy increasesdue to the effective nuclear charge increasing.
This is because the larger the effective nuclear charge, the stronger the nucleus is holding onto the electron and the more energy it takes to release an electron. There are some instances when this trend does not prove to be correct.
These can typically be explained by their electron configuration. For example, Magnesium has a higher ionization energy than Aluminum.
Magnesium has an electron configuration of [Ne]3s2. Magnesium has a high ionization energy because it has a filled 3s orbital and it requires a higher amount of energy to take an electron from the filled orbital.
Electron Affinity Electron affinity E. Electron affinity can further be defined as the enthalpy change that results from the addition of an electron to a gaseous atom. It can be either positive or negative value. The greater the negative value, the more stable the anion is.
Generally, the elements on the right side of the periodic table will have large negative electron affinity. The electron affinities will become less negative as you go from the top to the bottom of the periodic table.
However, Nitrogen, Oxygen, and Fluorine do not follow this trend.
The noble gas electron configuration will be close to zero because they will not easily gain electrons. The higher the electronegativity, the greater its ability to gain electrons in a bond. Electronegativity will be important when we later determine polar and nonpolar molecules.
Electronegativity is related with ionization energy and electron affinity. Electrons with low ionization energies have low electronegativities because their nuclei do not exert a strong attractive force on electrons.Ionization energy generally increases moving from left to right across an element period (row).
This is because the atomic radius generally decreases moving across a period, so there is a greater effective attraction between the negatively charged electrons and positively-charged nucleus. Experiment Overview The justification of this lab is to spot periodic trends in from SCIENCE at Legacy High School, North Las Vegas.
Aug 23, · The experiment we did was about Periodic Trends. We determined the trend of reactivity of nonmetals down a group, the trend of reactivity of metals along a period and the trend of acidic properties of elements along a period.
The halogens used were Cl2, Br2 and I2. Metals used were Sodium, Magnesium (magnesium ribbon), Status: Resolved. So the reactivity of metals decreases as you go from left to right and it increases as you go down on the periodic table.
Relating Reactivity of Metals to Atomic Structure. Let’s consider how metals react. Metals react by losing electrons. They have a low ionization energy so it's fairly easy for them to lose electrons. properties such as atomic radii, ionization energy, electron affinity, and electronegativity.
However, the periodic table can also be used to logically categorize many other atomic and ionic properties. However, since the ionization energy of guanine (in a GC pair) is 68 kJ less than that of adenine (in an AT pair), and since reaction 17 is thermodynamically unfavorable, it is unlikely that deprotonation would effect the location of the hole.