2.2 Molecules and Compounds Flashcards
What is a molecule?
formed when two or more atoms covalently bond together
What is a compound?
when atoms of two or more different elements bond together
What is an ion?
particles that are negatively or positively charged due to an electron transfer between atoms
What is an ionic bond?
the attraction between negatively and positively charged ions
What is a covalent bond?
when two atoms share electrons
What are the 3D shapes of molecules related to?
the structural and functional roles they play in organisms
What is a nonpolar covalent bond?
when the sharing of electrons between two atoms is fairly equal in a covalent bond
What is electronegativity?
the attraction of an atom for the electrons in a covalent bond
Why is water a polar molecule?
the shared pair of electrons spends more time around the nucleus of the oxygen atom than the hydrogen atoms because it is more electronegative
What is a polar covalent bond?
the unequal sharing of electrons in a covalent bond
What is a hydrogen bond?
a weak bond between hydrogen atoms and other atoms within the same molecule or between different molecules
What do hydrogen bonds between cellular molecules do?
help maintain their proper structure and function
ie. when DNA replicates, hydrogen bonds break easily, but they also add stability to the DNA molecule
