ch 1

Question 1

metals

Answer 1

most elements are metal; shiny, conduct metal and electricity.

Question 2

non metals

Answer 2

sulfur, chlorine, oxygen. have varied appearance and do not conduct well.

Question 3

noble gasses

Answer 3

inert element, does not undergo chemical reactions. (helium, neon, aragon)

Question 4

atomic number

Answer 4

protons

Question 5

atomic mass

Answer 5

protons + neutrons

Question 6

nucleus (3)

Answer 6

• neutrons: no charge.
  -protons: positively charged.
• both are of equal mass.

Question 7

electron shell

Answer 7

• electrons : negatively charged
• very light.

Question 8

an atom is neutral when:?

Answer 8

protons = #electrons

Question 9

hydrogen exception

Answer 9

contains one electron, one proton and no neutrons.

Question 10

isotopes

Answer 10

atoms of the same elements, with same number of protons and electrons but different number of neutrons so different mass.

Question 11

valency

Answer 11

combining power of atoms
number of electrons needed (gained, lost, or shared) to satisfy octet rule.

Question 12

valency gives rise to: (3)

Answer 12

-elements classified by: properties and atom number.
-groups (vertical): determine valency
-periods (horizontal)

Question 13

electrons in outermost shell responsibility

Answer 13

interactions between atoms to form molecules.

Question 14

covalent bonds

Answer 14

atoms sharing bonds

Question 15

ionic bonds

Answer 15

atoms gain or lose electrons

Question 16

cation

Answer 16

positive ion

Question 17

anion

Answer 17

negative ion

Question 18

electronegativity

Answer 18

a measure of an atom’s attraction for the electrons it shares in a covalent bond

—->
I. increases this way on periodic table.

Question 19

polar bonds

Answer 19

difference in atoms’ electronegativities in a bond creates a polar bond net dipole moment.

Question 20

a polar covalent bond

Answer 20

is a covalent bond in which the electrons are not equally shared but rather displaced towards the more electronegative atom.

Question 21

hydrogen bond

Answer 21

electrostatic attraction between atom bearing a partial positive charge in one molecule and an atom bearing a partial negative charge in a neighboring molecule.

Question 22

electrolytes

Answer 22

substances that will dissociate in solution

Question 23

intramolecular bonds

Answer 23

bonds existing within molecules (strong bonds)

Question 24

intermolecular bonds

Answer 24

bonds existing between molecules (weaker bonds)

Question 25

molecules

Answer 25

bringing more than one atom together

Question 26

compounds

Answer 26

if you bring two or more different atoms together

Question 27

all _ are _

Answer 27

all compounds are molecules but not all molecules are compounds

Question 28

covalent compounds

Answer 28

bonds formed where the shared electrons, are contributed from both atoms.

Question 29

coordinate/dative bonds

Answer 29

covalent bonds formed where the electrons are contributed by both atoms

Question 30

complexes

Answer 30

molecules that contain one or more of coordinate/ dative bonds

Question 31

coordination compounds

Answer 31

compounds that contain complexes.

Question 32

dative bond requirements (2)

Answer 32

- two atoms must be present as either (ion, atom or part of a molecule) - lewis acid + lewis base ---> complex

Question 33

lewis acid

Answer 33

atom that accepts electrons

Question 34

lewis base/ligand

Answer 34

atoms with a lone pair of electrons

Question 35

chelating agent (3)

Answer 35

-if ligands have more than one atom with a lone pair of electrons. - chemical that can form several bonds to a single metal ion - multidentate ligand - chemical that can form a soluble complex molecule

Question 36

lewis acid + chelating agent =

Answer 36

chelate (complex)

Question 37

porphyrin ring (4)

Answer 37

-chelate. -act as active sites -in chlorophyll A (for photosynthesis) -in hemoglobin (needed for mammalian respiration.

Question 38

EDTA (3)

Answer 38

- chelating agent - improve detergent efficiency - impose environmental threat by forming chelates with Pb and Hg, (soluble in water) -> making them available for uptake by living organisms.

Question 39

Molecular ions

Answer 39

molecules that carry net charge

Question 40

oxidation state (2)

Answer 40

- the actual charge on the atom or a notional charge (-,+,0) - the imaginary charge the atom would have if the shared electrons where divided equally between identical atoms and to the more electronegative atom in different atoms.

Question 41

organic compounds

Answer 41

compounds containing C and H covalently bonded together, and other elements.

Question 42

complexation reactions (6)

Answer 42

- also called "Lewis acid-base reaction" - result in dative bonds -lewis acid + lewis base = complex - metal + ligand = complex - Importance: affect availability of metal to organisms. i.e changes solubility of metals - humic material + cu (vital micronutrient) --> complex

Question 43

Acid-base reactions (5)

Answer 43

Bronsted Lowry - acid: H+ (proton) donors - bases: H+ (proton) acceptors / hydroxide donors - conjugate base: product remaining after acid loses proton - conjugate acid: product formed after base gains proton

Question 44

amphoteric

Answer 44

chemical that can act as either acid or base, based on reaction.

Question 45

Precipitation reaction (2)

Answer 45

- reactions that occur in solution in which one or more products are insoluble in solvent (mostly water) - important: affects chemicals, solubility, transfer, and toxicity

Question 46

Redox reactions (oxidation, reduction, redox process, oxidizing agent, reducing agent ) (5)

Answer 46

- oxidation: loss of electrons - reduction: gain of electrons -redox process: transfer of e's in the reaction - oxidizing agent: substance reduced in reaction - reducing agent: substance oxidized in reaction

Question 47

steps to balancing REDOX reactions (9)

Answer 47

1. write separate reduction, oxidation reactions. 2. for each half reaction: - balance elements (except O and H) - balance O with H2O - balance H using H+ - balance charge using electrons 3. if necessary, multiply by integer to equalize electron count. 4. add half reactions 5. check that elements and charges are balanced.

Question 48

Hydrolysis

Answer 48

reaction where one of its reactants is water - acid hydrolysis - basic hydrolysis -Importance: weathering of rocks.

Question 49

Free radical reactions (9)

Answer 49

- molecules mostly contain an even number of electrons- behaves as pairs -molecules that have one or more unpaired electrons is called "free radical" or "radical" - highly reactive - free radicals leads to chain reactions by producing other free radicals and other products. - radicals form as a result of: - collision with another molecule - collision with atom at high speed "thermal reaction" - absorbs light "photochemical reaction" - reacting with excited species.

Question 50

Atmospheric Ozone Depletion by CFCs (draw)

Answer 50

First, UV radiation breaks a carbon- halogen bond photon (λ < 220nm) + CCl2F2 ----> CClF2 + Cl- ( free radicals )

Question 51

Transumation Process

Answer 51

process: reactions that change the nuclei of one atom to another atom - nucleus 1 ---- nuclear reaction ----> nucleus 2 - nucleus of atom consist of nucleons (proton + neutrons) - Nuclear binding energy (E): energy holding the protons and neutrons together (released during nuclear rxn) - the higher the binding energy, the more stable the atoms. - E=mc^2

Question 52

Radioactivity vs Natural radiation ("background radiation)

Answer 52

Average annual dose to the general population. natural sources mainly radon, manmade sources mainly medical x - ray.

Question 53

sources of radiation (natural) (4)

Answer 53

- radon - internal - terrestrial - cosmic

Question 54

sources of radiation (man-made) (3)

Answer 54

- consumer product - nuclear medicine - medical x ray

Question 55

Types of Nuclear Reactions - nuclear fission

Answer 55

- Breaking apart of heavy nuclei to form two or more nuclei of roughly similar mass (total) + release of energy. - a few rxns do not need outside simulation - nuclear fission rxns can be simulated through neutrons

Question 56

Types of Nuclear Reactions - nuclear fusion

Answer 56

- Bringing together of two light nuclei + release of energy. - happens in the stars, naturally. - occurs on earth, artificially, by fast moving nuclei or nucleons.

Question 57

Types of Nuclear Reactions - nuclear Decay

Answer 57

disintegration of one nuclei into another (daughter nucleus) without external initiation (alpha, beta. gamma decay).

Question 58

Radioactive decay

Answer 58

when atoms ( with atomic number greater than 83, which are unstable) undergo spontaneous radioactive disintegration.

Question 59

Radioisotopes / radionuclides

Answer 59

- nuclei that undergo radioactive decay -produce radiation (alpha, beta, gamma) -may have harmful effects on environment and humans based on their energy.

Question 60

Chemical reactions vs nuclear reactions

Answer 60

C: atoms retain their identity N: atoms usually change from one element to another C: Reactions involve only electrons, usually only outermost electrons. N: reactions involve mainly protons and neutrons. valence electrons irrelevant. C: raising temp can speed up rxn rates N: rxn rates unaffected by temp changes. C: energy absorbed/given off by reactions is comparatively small. N: rxns sometimes involve enormous changes in energy. C: mass is conserved, the mass of products equals the mass of starting materials. N: huge changes in energy accompanied by measurable changes in mass (E=MC^2)