Week 2

Question 1

atoms

Answer 1

basic (smallest) structural units of elements

Question 2

elements

Answer 2

substance that cant be broken donw into simpler substance

Question 3

chemical rxn

Answer 3

processes that form/break bonds between atoms

Question 4

periodic table

Answer 4

organizes elements according to atomic #/chemical characteristics

Question 5

atoms are made up of __ subatomic particles

Answer 5

3 (neutrons/protons/electrons)

Question 6

__ are found in the inner most core (nucleus) of the cell

Answer 6

protons/n`eutrons

Question 7

of protons should

Answer 7

equal # of electrons

Question 8

atomic # will ..

Answer 8

always equal # of protons

Question 9

mass #

Answer 9

sum of protons + neutrons

Question 10

merucry causes __ nerve cells

Answer 10

denuded nerve cells

Question 11

isotopes

Answer 11

atoms of elements w/ diff # of neutrons
- each has diff mass # of neutrons

Question 12

radioactive

Answer 12

nuclei spontaneousl break part (releases energy)

Question 13

nuclei provide stability by

Answer 13

remaining uncharged (the protons/neutrons) during chem rxn

Question 14

electeons are repsonsible for

Answer 14

interactions among atoms

Question 15

the electrons close to the nucleus are

Answer 15

low energy and inner-most shell can only carry 2 electrons

Question 16

the electrons in the outermost shell are

Answer 16

high energy

Question 17

electron absorbs energy from sunlught, uv rays, etc..

Answer 17

is then boosted to a higher shell, then drops back into lower enery shell and then releases energ as heat and light (like bioluminescence)

Question 18

molecules

Answer 18

made up of 2 or more atoms

Question 19

atoms form molecues to

Answer 19

fill vacancies in outer electron shells

Question 20

atom wont react w/ other atoms …

Answer 20

if outermost shell is full
(these are called inert (stable) atoms)

Question 21

__ is highly electronegative

Answer 21

oxygen (lieks taking electrons from other atoms)

Question 22

free radicals

Answer 22

atom whose outermiost shell is partially full (can contribute to aging/death since they can be so reactive)

Question 23

__ bonds hold atoms together in molecules

Answer 23

chemical

Question 24

chemical bonds

Answer 24

attract forces that hold atoms together (atoms gain/lose/share electrons)

Question 25

ionic bonds

Answer 25

attraction where electron is transferred ex: salt (NaCl)

Question 26

covalent

Answer 26

electrons are shared between atoms

Question 27

nonpolar covalent

Answer 27

electrons shared equally betwen atoms ex: CO2/ ex: hydrogen atom + hydrogen atom - are also less likely to dissolve

Question 28

polar covalent

Answer 28

electrons are shared unequally ex: H2O

Question 29

hydrogen bonds

Answer 29

attraction between polar nolecules where hydrogen is bonded to olxygen/nitrogen - these bonds are very weak and can break when heat is increased!

Question 30

octet rule

Answer 30

8 electrons in outer shell ex: table salt is ionic

Question 31

hydrigen bonds in water cause

Answer 31

cohesion

Question 32

cohesion

Answer 32

tendency of water molecules to stick together ' - also produces surface tension

Question 33

surface tension

Answer 33

tendency for water molecule to resist being broken

Question 34

water has __ prpoerties

Answer 34

cohesive/adhesive - water will move up a root of a plant due to cohesive properties (capillary action)

Question 35

mercury has __ forces but not __

Answer 35

cohesive but not adhesive, which is better for a thermometer

Question 36

blood is both __ and __

Answer 36

cohesive/adhesive has lots of water

Question 37

water is a very important ..

Answer 37

solvent

Question 38

oil/water dont mix cuase of

Answer 38

nonpolar electrons

Question 39

pH

Answer 39

power of Hydrogen

Question 40

Water breaks down into

Answer 40

hydroxide/hydrogen ion

Question 41

hiw to say the pH of a solution:

Answer 41

the concentration of H+ ions versus the amount of OH- ions

Question 42

acidic solution

Answer 42

H+ excees OH- -an acid releases H+ when dissolves in water ex: lemon juice

Question 43

basic solution

Answer 43

OH- exceed H+ - a base increases OH- solution when dissolved in water ex: socium hydroxide separates into both sodium and hydroxide in water

Question 44

neutral solution

Answer 44

equal balance between H+ and OH- ex: water (pH is 7) blood/milk are neutral to an extent - blood = 7.4 - milk = 6.4