Meningioma; Synonyms: Meningeal tumor: A contrast-enhanced CT scan of the brain, demonstrating the appearance of a meningioma: Specialty: Neurosurgery: Symptoms: None, seizures, dementia, trouble talking, vision problems, one sided weakness: Usual onset: Adults: Types: Grade I, II, III: Risk factors: Ionizing radiation, family history: Diagnostic method
A polar covalent bond shares electrons unequally. Because of this unequal sharing, one end of the molecule is slightly positive, and the other end slightly negative. Edit
Atoms in a covalent bond are held together by electrostatic forces of attraction between positively charged nuclei and negatively charged shared electrons. Electronegativity (see Patterns in the Periodic Table) is the measure the attraction of an atom involved in a bond has for the electrons of the bond. When two atoms bonded by a covalent bond have the same electronegativity the electrons will be equally shared. This is called pure (non-polar) covalent bonding.