Classification of Crystalline Solids

ionic crystals are composed of:

• atoms
• molecules
• covalent bonds
• ions

which of the crystals are brittle:

• ionic

• covalent

• atomic

• molecular

ionic crystals don't conduct electricity in dry and solid state why:

• Ions in ionic crystals are not charged.
• Ionic crystals are not solid in nature.
• Ionic crystals do conduct electricity in dry and solid state.
• Ions are held in fixed positions and cannot move freely to carry the electric charge.

In ionic crystal, the charge carrier for electrical conduction are:

• ions
• neutrons
• protons
• electrons

Covalent crystals are formed between:

• atoms
• compounds
• ions
• molecules

Diamond & Graphite are the example of which class of crystal:

• ionic crystal

• covalent crystal

• atomic crystal

• molecular crystal

Diamond is the hardest substance because:

• Diamond has weak covalent bonds between carbon atoms
• Diamond is made up of soft materials
• Diamond is a liquid substance
• Strong covalent bonds between carbon atoms

Graphite is good conductor of electricity because:

• Graphite has a low atomic number
• Sp² hybridization & Delocalized electrons

• Graphite has a high melting point
• Graphite has a high density of protons

Graphite conducts electricity ____ to the hexagonal layers:

• perpendicular
• diagonally
• randomly
• parallel

Metallic bonding occurs between:

• covalent compounds
• metal cations & sea of electrons

• ionic compounds
• non-metal atoms