Topic 2 Flashcards
Atomic number
Number of protons in an atom
Mass number
Sum of protons and neutrons in an atom
Atomic mass
The average mass of all naturally occurring isotopes
Ions
Atoms that have given up or gained an electron in their outer electron shell
Molecules
Formed when atoms share electrons
Ionic bonds
Form when an atom loses or gains a valence electron
Covalent bond
Atoms share electrons rather than gain/lose them
Single covalent
2 atoms share 1 electron pair
Double covalent
2 atoms share 2 pairs of electrons
Triple covalent
2 atoms share 3 electron pairs
Nonpolar covalent
Electrons are shared equally
Polar covalent
Unequal sharing of electrons
Hydrogen bonds
Polar covalent bonds that form between hydrogen atoms and other atoms
Chemical bonds (what do they do)
Forces that hold the atoms of a molecule together
3 types of chemical bonds
Ionic, covalent, hydrogen
Chemical reactions
Occur when electrons in valence shell are shared/transferred. New bonds form and/or old bonds are broken
Exergonic reaction
Releases energy
Endergonic reaction
Requires energy
Catalysts
Chemical compounds that speed up chemical reactions by lowering the activation energy needed for a reaction to occur
Synthesis reaction
A+B -> AB
Decomposition reactions
AB -> A+B
Exchange reactions
AB+CD -> AD+CB
Reversible reactions
AC A+C
Metabolism
Sum total of all chemical reactions in the body