For each, give the total number of electrons, the number of valence electrons, and the number of the energy level that holds the valence electrons.
Br-35 electrons--7 valence--4th level
Kr-36 electrons--8 valence--4th level
As-33 electrons--5 valence--4th level
I-53 electrons--7 valence--5th level
These look ok to me.
To determine the total number of electrons, the number of valence electrons, and the number of the energy level that holds the valence electrons for each element, you need to understand the structure of the periodic table.
1. Br (Bromine) - Atomic number: 35
- Total number of electrons: The atomic number represents the total number of electrons in a neutral atom, so there are 35 electrons in Bromine.
- Valence electrons: Bromine belongs to Group 7A (17) in the periodic table, so it has 7 valence electrons.
- Energy level of valence electrons: Valence electrons are typically found in the highest principal energy level, which for Bromine is the 4th level.
2. Kr (Krypton) - Atomic number: 36
- Total number of electrons: Krypton has 36 electrons based on its atomic number.
- Valence electrons: Krypton is in Group 8A (18) of the periodic table, meaning it has 8 valence electrons.
- Energy level of valence electrons: As with Bromine, the valence electrons are in the highest principal energy level, which is the 4th level for Krypton.
3. As (Arsenic) - Atomic number: 33
- Total number of electrons: The atomic number of Arsenic is 33, indicating it has 33 electrons.
- Valence electrons: Arsenic belongs to Group 5A (15) in the periodic table, so it has 5 valence electrons.
- Energy level of valence electrons: The valence electrons are located in the 4th level for Arsenic.
4. I (Iodine) - Atomic number: 53
- Total number of electrons: Iodine contains 53 electrons based on its atomic number.
- Valence electrons: Iodine is part of Group 7A (17), leading to 7 valence electrons.
- Energy level of valence electrons: Valence electrons in Iodine are found in the 5th level, which is the highest energy level.
To summarize:
Br: Total electrons = 35, Valence electrons = 7, Energy level of valence electrons = 4th level
Kr: Total electrons = 36, Valence electrons = 8, Energy level of valence electrons = 4th level
As: Total electrons = 33, Valence electrons = 5, Energy level of valence electrons = 4th level
I: Total electrons = 53, Valence electrons = 7, Energy level of valence electrons = 5th level