Question

periodic table basics
name braedeb prebell

1. which elements had complete outer shells? give the name and symbol for each.
2. what do you notice about the location of the elements in #1?
3. which elements had only one valence electron?
4. what do you notice about the location of the elements in #3?
5. what do you notice about the number of valence electrons as you move from left to right across a row or period in the periodic table? (na → mg → al → si → p → s → cl → ar)
6. what do you notice about the number of energy levels or shells as you move down a group or column in the periodic table? (h → li → na)
7. elements are organized into families according to their physical and chemical properties. identify the elements that you used in step 5 that belong to each family based on the number of valence electrons. give the name and symbol for each element.

alkali metals - 1 valence electron &
alkaline earth metals - 2 valence electrons &
boron family - 3 valence electrons &
carbon family - 4 valence electrons &
nitrogen family - 5 valence electrons &
oxygen family - 6 valence electrons &
halides - 7 valence electrons &
noble gases - complete outermost shell &

1. what do you notice about the location of the elements in each family?
2. how would you classify hydrogen? why?
3. predict the number of valence electrons for each element based on its location in the periodic table of elements. you will need to use the table in your textbook.

barium = lead = xenon = potassium =
t. trimpe 2002

Explanation:

Step1: Identify noble gases

Noble gases have complete outer - shells. Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), Radon (Rn).

Step2: Location of noble gases

They are in Group 18 of the periodic table.

Step3: Identify elements with one valence electron

Alkali metals (Group 1) have one valence electron. Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs), Francium (Fr).

Step4: Location of elements with one valence electron

They are in Group 1 of the periodic table.

Step5: Analyze valence electrons across a period

As you move from left to right across a period, the number of valence electrons increases by 1.

Step6: Analyze energy levels down a group

As you move down a group, the number of energy levels or shells increases by 1.

Step7: Categorize elements by valence - electron number

Alkali Metals: Sodium (Na); Alkaline Earth Metals: Magnesium (Mg); Boron Family: Aluminum (Al); Carbon Family: Silicon (Si); Nitrogen Family: Phosphorus (P); Oxygen Family: Sulfur (S); Halides: Chlorine (Cl); Noble Gases: Argon (Ar)

Step8: Location of family elements

Elements in the same family are in the same group of the periodic table.

Step9: Classify hydrogen

Hydrogen can be considered in a unique category. It has 1 valence electron like alkali metals but is a non - metal under normal conditions.

Step10: Predict valence electrons

Barium (Ba) is in Group 2, so 2 valence electrons; Lead (Pb) is in Group 14, so 4 valence electrons; Xenon (Xe) is in Group 18, so 8 valence electrons; Potassium (K) is in Group 1, so 1 valence electron.

Answer:

1. Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), Radon (Rn)
2. They are in Group 18.
3. Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs), Francium (Fr)
4. They are in Group 1.
5. The number of valence electrons increases by 1.
6. The number of energy levels or shells increases by 1.
7. Alkali Metals: Sodium (Na); Alkaline Earth Metals: Magnesium (Mg); Boron Family: Aluminum (Al); Carbon Family: Silicon (Si); Nitrogen Family: Phosphorus (P); Oxygen Family: Sulfur (S); Halides: Chlorine (Cl); Noble Gases: Argon (Ar)
8. Elements in the same family are in the same group.
9. It can be considered unique; has 1 valence electron like alkali metals but is a non - metal under normal conditions.
10. Barium = 2; Lead = 4; Xenon = 8; Potassium = 1