Quiz 1 Chemistry Flashcards
atoms’ 3 subatomic particles
protons--atomic mass of 1
charge: positive
electrons--atomic mass of 0
charge: negative
neutrons--atomic mass of 1
charge: neutralthe octet rule
- atoms like to have filled outer valence levels
- they are willing to gain or lose electrons in order to achieve this
- once they do this, they no longer are stable, neutral elements, but rather, charged ions
- negative charge (gain e-)=anion
- positive charge (lose e-)=cation
ionic bonding:
oxidation v. reduction
- when electrons are transferred btwn 2 or more atoms
- when an atom loses an e- it becomes positive so it is OXIDIZED
- when an atom gains an e- it becomes negative so it is REDUCED.
- redox bonds–coupled rxns–> if something is oxidized, something else is reduced
major elements
four most common in body
C-O-H-N carbon oxygen hydrogen nitrogen
mineral elements
(7 smaller elements of the body
Magnesium Mg Sulfur S Phosphorus P Potassium K Sodium Na Calcium Ca Chlorine Cl *pneumonic--Make sure pretty people stop catching cholera
types of bonds`
- ionic
- non-polar covalent
- polar covalent
- hydrogen bonds
Ionic bonds
-complete transfer of electrons
-separate ions (charged particles) form
-less stable bonds–common for them to dissolve in water (a great solvent)
ex. Na and Cl
not very stable alone–don’t have full outer e level
but with an ionic bond, their levels become full and they become very stable ions
Na+ Cl- = table salt!
non-polar covalent bonds
- EQUAL sharing of electrons–> atoms give the same number they receive
- always share in pairs/multiples of 2.
- no +/- charge because e- never leave the atom, but rather sit on the border of the two.
- charge balanced among atoms
- very stable
- humans are made of covalent bonds
ex. CO2 - carbon is the backbone of covalent bonds!
- carbon, hydrogen and silicon are often in covalent bonds because they have half-filled valence levels so its not easy to lose or gain e, so they share!)
polar covalent bonds
- unequal sharing of e-
- slight (-) charge at one end of molecule, and slight (+) charge at other end
ex. H2O
properties of water
- polar covalent bond
- has covalent and ionic properties
- dipole: has a positive and negative end
- it is cohesive–molecules align and “stick together” due to polarity–negatives stick to positives etc
- it is adhesive in that it can wet things
- widest temp. range as a liquid for any molecule (0-100 centigrade!) making life possible.
- able to stabilize ions in solution (electrolytes) (able to conduct electricity)
- tends to dissolve ionic bonds (its a great solvent)
hydrogen bonds
- electropositive hydrogen (H+) attracts an electronegative atom
- both hydrogen and the electronegative ion it attracts are usually part of a larger compound.
- water forms hydrogen bonds with itself which gives it many of its properties
ex. H+ and OH- =H2O
types of chemical reactions (3)
- oxidation-reduction rxns
- anabolic rxns–an uphill rxn
- requires outside energy to start
- produces more complex product from the reagents
- catabolic rxns–downhill rxn
- releases energy to the enviro
- produces simpler product from reagents
*anabolic needs “an”-other source of energy to push it uphill.
*catabolic has it’s own catalyst and goes on its own downhill.
*-cats- are low maintenance–require less external energy,
kittens (reagents) more complex/needy than adult cats (products)
entropy
- disorder!
- most rxns favor disorder
acid-base-salt formula
acid + base –> salt + water
- acids are proton(H+) donors
- bases are hydroxyl(OH-) donors
-in order to be donors, acids and bases must be dissolved in water, which allows them to ionize
common acids
- HCl hydrochloric acid H+ + Cl-
- HNO3 nitric acid H+ + NO3-
- H2SO4 sulfuric acid 2H+ + SO4^-2
- H3PO4 phosphoric acid 3H+ + PO4^-3
- H2CO3 carbonic acid 2H+ + CO3^-2
