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
Covalent bonds occur when the sharing of electrons acts to hold atoms together. However if two different atoms are being bonded then the electrons will not âhang outâ evenly between them. As a rule of thumb the smaller atoms tend to pull more tightly on electrons than larger ones. So the smaller atom in a bonded pair will tend to hog up more than its share of electrons. The atom that holds more tightly onto electrons will have a small negative charge while the other will have a slight positive charge. A covalent bond is consider polar when this inequality in electron sharing becomes significant.