Metals usually become cations since electrons are negatively charged and when they are lost there are more protons than electrons making a positive net charge in the atom. (cations are positively charged ions while anions are negatively charged ions)
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Answer:
highest first ionization energy - Br
smallest atomic size - Br
most metallic character - Na
Explanation:
Ionization energy of Br is higher than P because higher zeff value
Sodium is more metallic than calcium because it is able to loose electron more readily as compared to calcium because of higher electro positivity.
Atomic radius of Br is the smallest as its atomic radius is 114, P (115), Ca (197), Na (186)
Hydrogen is a nonmetal and is placed above group in the periodic table because it has ns1 electron configuration like the alkali metals. However, it varies greatly from the alkali metals as it forms cations (H+) more reluctantly than the other alkali metals.Aug 15, 2020
Electronic Configuration: 1s
At Room Temperature: Colorless & Odorless Diatomic Gas
Atomic Weight: 1.0079