The strength of metallic bonds depends on the

Analyze the question: It asks which factor determines how strong the metallic bond is in a metal.

Concept: A metallic bond is the electrostatic attraction between positive metal ions (the lattice of cations) and the "sea" of delocalised valence electrons around them. The strength of this attraction depends on:

1. The number of valence electrons each atom donates to the electron sea. More delocalised electrons mean a stronger attraction.
2. The charge and size of the cation (ionic radius). A higher charge and a smaller radius give a stronger bond.

Solution:

• A. Charge density of the atoms: Charge density of the ions does influence bond strength, but the question says "atoms", and atoms are neutral. This option is imprecise.
• B. Ductility of the metal: Ductility is a result (a property) of metallic bonding, not a cause of its strength.
• C. Number of valence electrons: This is the standard answer. For example, sodium (1 valence electron) has a weak metallic bond and is soft with a low melting point. Magnesium (2) and aluminium (3) have progressively stronger bonds, higher melting points and more hardness.
• D. Total number of electrons in the atom: Only the valence electrons are delocalised, so inner electrons don't contribute to the bond.

Answer: C. number of valence electrons

Tip: Remember the trend Na < Mg < Al. As valence electrons increase from 1 to 3, melting points rise from 98°C to 650°C to 660°C. Whenever WASSCE asks what metallic bond strength depends on, think "valence electrons (and ion size)". Properties like ductility are consequences, never causes.