dic Trends Pre-laboratory work: What common feature exists in the electronic structure of elements in group 2? How about group 6? Similar to Tro page 339 for group 2, what might be the common formula for the oxide? For group 6, what would be the common formula for the chloride? . When Mendeleev first discovered the periodic table, the noble gasses where not known How did this discovery alter the periodic table and what key quantum concept does this emphasize? Find the formulas for the anhydride of each of the following molecules. To obtain the formula of an anhydride, subtract H2O units from the formula until all hydrogens have been subtracted. If the molecule has an odd number of hydrogens, double its formula . first. a. H2SO4 EXAMPLE: Subtracting one H20 unit from H2SO, leaves SO,. This is the anhydride for this acid. Follow this procedure for the remaining acids below:
Solution
3. When Mendeleev first predicted Periodic Table the Noble gases were not discovered. After the discovery of Helium and Argon. Mendeleev included it as Group 0.
Quantum mechanical solution
The modern explanation why the elements fall into vertical columns, showing similar properties, has been provided by quantum mechanics and describes the shell structure of electrons orbiting the nucleus of each kind of atom.
The elements in group 1, for example, all have one outer-shell electron although they differ in their inner shell structures.
Lithium 1s2 2s1
Sodium 1s2 2s2 2p6 3s1
Potassium 1s2 2s2 2p6 3s2 3p6 4s1
It is the outer-shell electrons which govern their chemical properties and that\'s why they behave similarly. For instance, all these metals react with water, although the reactivity increases as one descends the group from lithium to potassium and beyond to caesium and rubidium.
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dic Trends Pre-laboratory work- What common feature exists in the elec (1).docx
1. dic Trends Pre-laboratory work: What common feature exists in the electronic structure of
elements in group 2? How about group 6? Similar to Tro page 339 for group 2, what might be
the common formula for the oxide? For group 6, what would be the common formula for the
chloride? . When Mendeleev first discovered the periodic table, the noble gasses where not
known How did this discovery alter the periodic table and what key quantum concept does this
emphasize? Find the formulas for the anhydride of each of the following molecules. To obtain
the formula of an anhydride, subtract H2O units from the formula until all hydrogens have been
subtracted. If the molecule has an odd number of hydrogens, double its formula . first. a. H2SO4
EXAMPLE: Subtracting one H20 unit from H2SO, leaves SO,. This is the anhydride for this
acid. Follow this procedure for the remaining acids below:
Solution
3. When Mendeleev first predicted Periodic Table the Noble gases were not discovered. After the
discovery of Helium and Argon. Mendeleev included it as Group 0.
Quantum mechanical solution
The modern explanation why the elements fall into vertical columns, showing similar properties,
has been provided by quantum mechanics and describes the shell structure of electrons orbiting
the nucleus of each kind of atom.
The elements in group 1, for example, all have one outer-shell electron although they differ in
their inner shell structures.
Lithium 1s2 2s1
Sodium 1s2 2s2 2p6 3s1
Potassium 1s2 2s2 2p6 3s2 3p6 4s1
It is the outer-shell electrons which govern their chemical properties and that's why they behave
similarly. For instance, all these metals react with water, although the reactivity increases as one
descends the group from lithium to potassium and beyond to caesium and rubidium.
