Lithium, beryllium, boron, and fluorine are four elements in Period 2 on the Periodic Table. State,

NY Regents Chemistry Exam June 2022

Lithium, beryllium, boron, and fluorine are four elements in Period 2 on the Periodic Table.

57 State, in terms of electrons, why the radius of a Be2+ ion is smaller than the radius of a Be atom. [1]

Be^2+ has a positive 2 charge which means it lost two electrons

Answer? Be2+ ion is smaller than the radius of a Be atom because is has two less electrons.

58 Draw a Lewis electron-dot diagram for an atom of boron. [1]

Boron's electron configuration is 2-3 according to the Periodic Table on the Reference Table. Therefore, it has 3 valence electrons (the electrons in the outmost shell). We represent valence electrons as dots.

Lewis electron-dot diagram for an atom of boron

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