Covalent and metallic bonding Flashcards
Covalent bond is bond formed by….
sharing of electrons between two atoms
Can covalent bonds form with metals?
No. Just no. Ionic and metallic can though.
Why simple molecular structures have low M.pt and B.pt?
between molecules there are only weak intermolecular forces holding them together, these forces can be easily overcame
Why simple molecular structures do not conduct electricity in any state?
they do not have any free moving electrons/ ions to conduct electricity
Simple molecular structures are usually insoluble in??
Water, soluble in organic solvent though
EXAMPLES of giant and simple molecular structures.
Giant:
diamond, graphite, silicon dioxide
Simple:
crayon, bromine
Why giant molecular structures have very high M.pt and B.pt?
they are held together by strong covalent bonds
to melt/boil, these bonds must be broken
hence require large amt of energy
Why is graphite different from other giant molecular structures?
Graphite can conduct electricity, others cannot because they have no free electrons to conduct electricity
Metallic bond is…
force of attraction between positive metal ions and the ‘sea of mobile electrons’
Why are metals good conductor of electricity & heat?
outer electrons of atoms can break away easily from atoms. outer electrons can move freely within metal lattice, electricity and heat energy easily transferred
Why are metals malleable and ductile?
when a force is applied to a metal, the layers lf metal atoms can slide over each other through the ‘sea of electrons’
