Question
Which series shows the correct order of metallic bond strength from strongest to weakest?
A Na > K > Rb > Mg
B Mg > Rb > K > Na
C Rb > K > Na > Mg
D Mg > Na > K > Rb
▶️Answer/Explanation
Ans: B
A metallic bond is a type of chemical bond created by positively charged atoms sharing their free electrons among a lattice of cations. The most common chemical bond between metal atoms is metallic bonding.
Potassium comes after Sodium in IA group and has more reactivity. So, K forms a strong metallic bond.
As we move down the group atomic radius increases so the metallic character also increases. Rb has stronger metallic bond than K.
In Mg, two valence electrons each are present. In Rb, K and Na, only one valence electron is there. So, bond strength is highest in Mg.
Question
Zinc metal contains metallic bonding. Which is the best description of a metallic bond?
A. The electrostatic attraction between a pair of electrons and positively charged nuclei.
B. The electrostatic attraction between oppositely charged ions.
C. The electrostatic attraction between a lattice of positive ions and delocalized electrons.
D. The bond formed when one atom provides both electrons in a shared pair.
▶️Answer/Explanation
C
Metallic bonding is the electrostatic attraction between a lattice of positive metal ions and a sea of delocalized electrons.
Question
A solid has a melting point of 1582 °C and does not dissolve in water. It does not conduct electricity in the molten state. What type of structure does the solid have?
A. Ionic
B. Metallic
C. Giant molecular
D. Simple molecular
▶️Answer/Explanation
C
Since it does not dissolve in water and it does not conduct electricity in the molten state, it is not an ionic structure compound.
Which means it is a covalent structure compound and as it also has a high melting point, it is a giant molecular covalent compound.
Question
Which metal has the strongest metallic bonding?
A. Na
B. Mg
C. Al
D. Ca
▶️Answer/Explanation
C
Bond strength is highest in Al, due to the presence of three valence electrons, In Mg and Ca, two valence electrons each are present. In Na, only one valence electron is there.