Periodic trends assignment(2020) PDF

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Periodic Trends Assignment Create properly labelled graphs (using a spreadsheet program of your choice) to show trends of a) ionization energy and b) electronegativity when plotted against atomic number using the data for the first 56 elements. Be sure to understand the definitions for I.E. and EN. Based on your graphs and an examination of the data, summarize the trends by completing the following: 1. Atomic Radius Trend Trend Down Group Atoms get bigger as What the data you go down a column says: on the periodic table. Suggest a reason This is because in for the pattern going down a column you are jumping up to the next higher main energy level and each energy level is further out from the nucleus that is, a bigger atomic radius.

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Trend Across Period Atoms get smaller as you go across a row from left to right. The logic is that as you go across rows, you are staying in the same main energy level so electrons are entering the atomic atmosphere at about the same distance. However, as you go across, the nuclei are getting more and more positive (more protons) therefore there is more + to – attraction and the electron cloud is pulled in tighter and therefore a smaller radius.

Deviations (if any) There are some small exceptions such as the oxygen radius being slightly greater than the nitrogen radius.

2. Ionic Radius Trend What the data says: Suggest a reason for the pattern

Trend Down Group Trend Across Period The radius increases as The radius decreases as you move down columns. you move from left to right. Ionic radius is the The same trend as the distance away from the Atomic Radius trend, so central atom. So if the this also decreases. atomic radius increases this also increases.

3. Ionization Energy Trend Trend Down Group What the graph Ionization energy says: decreases as you go down a group. Suggest a reason for the pattern

This is because the outermost electron is, on average, farther from the nucleus, meaning it is held less tightly and requires less energy to remove.

Trend Across Period Ionization energy increases as you go from left to right. The ionization energy of an element increases as one moves across a period in the periodic table because the electrons are held tighter by the higher effective nuclear charge. This is because additional electrons in the same

Deviations (if any) Oxygen.

Deviations (if any) Exceptions to this trend are observed for alkaline earth metals (group 2) and nitrogen group elements (group 15).

shell do not substantially contribute to shielding each other from the nucleus, however an increase in atomic number corresponds to an increase in the number of protons in the nucleus. 4. Electronegativity Trend Trend Down Group What the graph EN decreases as you go says: down a group. Suggest a reason From top to bottom for the pattern down a group, electronegativity decreases. This is because atomic number increases down a group, and thus there is an increased distance between the valence electrons and nucleus, or a greater atomic radius.

Trend Across Period EN increases as you move from left to right. The positively charged protons in the nucleus attract the negatively charged electrons. As the number of protons in the nucleus increases, the electronegativity or attraction will increase. Therefore electronegativity increases from left to right in a row in the periodic table.

Deviations (if any) Noble Gasses since they don’t bond because they have full valence shell electrons so they are really stable. Lanthanides and Actinides are also exceptions.

5. A meteor crashed into the desert in Arizona. The scientists who discovered it performed tests to determine what elements were in the meteor. ● The most abundant element has an ionic radius 1.95 times larger than its atomic radius. ● Its 6th ionization energy is over 5 times larger than the 5th ionization energy. ● It has an electronegativity value greater than 3.00 Paulings. ● Suggest a candidate for this element. I believe it’s Nitrogen. It’s ionic radius is like 30 and it’s atomic radius is 155pm. It’s 5th ionization energy is 9,444.9 and 6th is 53,266.6 which is roughly about 5x times bigger. It’s EN value is also 3.04 Paulings. 6. A sample contains an unknown element. ● The ionic radius of the unknown element is smaller than its atomic radius. ● Its electronegativity is between 0.70 and 1.00 Paulings. ● It is extremely reactive and has an atomic mass of less than 35 g/mol. ● Suggest a candidate for this element. A solid candidate for this element is Sodium (Na). Sodium’s ionic radius is smaller than it’s atomic radius. It has an EN value of 0.93 Paulings. It’s atomic radius is 22.98977 g/mol.

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Time spent on assignment: I finished a few days ago but question 6 was remaining and I forgot about it when week 2 started. Today is Tuesday September 21, 2021 and I’m done. My resources for this assignment were the periodic table and Google. Well, I looked up stuff about the periodic table on Google....