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
The bonds between carbon and hydrogen atoms are also nonpolar, such as the four CâH bonds in a methane molecule (Figure 2.5 d). In a polar covalent bond , the sharing of electrons between two atoms is unequalâthe nucleus of one atom attracts the shared electrons more strongly than the nucleus of the other atom. When polar covalent bonds form, the resulting molecule has a partial negative charge near the atom that attracts electrons more strongly.