LQB182 MidSem Exam (QUESTIONS AND ANSWERS )2022/2023

Valance shell Outermost electron shell and its electrons determine chemical behaviour and bonding Radioactive isotopes Useful in medical diagnostic tests and in research Atoms can gain or lose electrons ... Metals lose electrons and non-metals accept ... Anions negatively charged ions (gain electrons) Cations positively charged ions (lose electrons) Intramolecular bonds Strong bonds - ionic, covalent, or metallic bonds Intermolecular bonds Weak bonds - hydrogen, dipole-dipole, or London dispersion forces (Van der Waals) Ionic bonds electrons are not shared equally. Strong Covalent bonds electrons shared equally. Strong Metallic bonds metal ions share electrons. Strong Hydrogen bonds occurs when a hydrogen atom in one molecule is attracted to the electrostatic atom in another molecule. Weak Dipole-dipole attractions between oppositely charged regions of polar molecules. Weak