Which element has the same number of valence electrons as bromine (Br)?
• chlorine (Cl)
• potassium (K)
• krypton (Kr)
• selenium (Se)
all the halogens have 7 valence electrons
chlorine
Chlorine (Cl) has the same number of valence electrons as bromine (Br). Both bromine and chlorine belong to Group 17 of the periodic table, also known as the halogens.
To determine which element has the same number of valence electrons as bromine (Br), we need to look at the group number on the periodic table. Valence electrons are the electrons located in the outermost shell of an atom.
Bromine is located in Group 17, also known as the halogens. Elements in Group 17 have 7 valence electrons.
Now, let's analyze the options:
• Chlorine (Cl) is also located in Group 17, like bromine. Therefore, it also has 7 valence electrons, making it a potential candidate.
• Potassium (K) is located in Group 1. Elements in Group 1, also known as alkali metals, have 1 valence electron. Therefore, it does not have the same number as bromine.
• Krypton (Kr) is located in Group 18, also known as the noble gases. Elements in Group 18 have 8 valence electrons, except for helium, which has 2. Therefore, krypton does not have the same number as bromine.
• Selenium (Se) is located in Group 16. Elements in Group 16, also known as the chalcogens, have 6 valence electrons. Therefore, selenium does not have the same number as bromine.
From the options provided, only chlorine (Cl) has the same number of valence electrons as bromine (Br), which is 7.