Chapter 2

Question 1

law of definite proportions

Answer 1

elements always combine in DEFINITE proportions by mass to form a compound. meaning..
C and H will always combine in a definite proportion by MASS*** no matter how many moles each

Question 2

law of multiple proportions (ratio of ratios)

Answer 2

if elements form more than one compound, those compounds will have compositions (%) that are WHOLE # multiples of each other

C3H8 times 1.5 is C5H12

Question 3

Coulomb’s Law and equation

Answer 3

-the energy of attraction or repulsion between two particles is directly proportional (constant ratio) to the product of the charges
-as distance increases, charges decrease

F= energy of attraction
q=charges
r=distance

Question 4

electrical charge and electrostatic forces

Answer 4

electrical charge: property of some particles that compose atoms- results in attractive/repulsive forces between those particles

electrostatic forces: attractive/repulsive forces that exist around a CHARGED PARTICLE

Question 5

order of the 6 models of the atom

Answer 5

1. Dalton
2. J.J Thompson (C.C. cookies)
3. Rutherford’s
4. Bohr’s
5. Wave mechanical

Question 6

in terms of subatomic particles, how does an atom of Cu-63 differs from an atom of Cu-65

Answer 6

different # of neutrons, same # of protons and electrons
protons+neutrons = isotope notation

Question 7

what letters represent protons, neutrons, electrons

Answer 7

Z= atomic number (protons)
A= mass number (protons and neutrons)
N= neutrons

Question 8

where are the…located on the periodic table?
-alkali metals
-alkali EARTH metals
-halogens
-transition metals

Answer 8

alkali metals: group 1
alkali earth metals: group 2
halogens: group 17
transition metals: groups 3-11

Question 9

characteristics of transition metals

Answer 9

-can have multiple oxidation states
-ions in solution are (typically) colorful

Question 10

elements that are gases at STP

Answer 10

group 18 and H O N Cl F
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Question 11

liquids at STP

Answer 11

Mercury and Bromine
Hg, Br

Question 12

all the diatomic elements

Answer 12

H, O, N, Cl, F, I, Br
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Question 13

Mass spectrometry

Answer 13

-used for studying unknown substances
-breaks compounds into smaller fragments and separates these according to mass, then exact composition is determine

can determine the **molar mass of a compound and provide additional information about **compound’s composition

Question 14

Mole map

Answer 14

used to convert moles to mass (gfm), volume (L), and atoms (particles)

1 mole= 22.4 L
1 mole= 6.022 x 10^23 particles

Question 15

Dalton’s atomic theory

Answer 15

1. each element has tiny, indestructible atoms
2. all atoms of a given element have the same mass (other properties distinguish them from other elements)
3. atoms combine in whole-number ratios
4. atoms of one element cannot change into atoms of another element

Question 16

JJ Thomson’s theory of the atom and experiment

Answer 16

experiment led him to observe..
-particles travel in straight lines
-particles carry a negative electrical charge
-particles are independent of the composition of the cathode
CONCLUSIONS:
1. negative subatomic particles are present in an atom (electrons)
2. determined charge/mass ratio of an electron

Question 17

1 atomic mass unit (amu) is equal to how many carbon atoms?

Answer 17

1 amu= 1/12 mass of a carbon atom

Question 18

which level of PE (high or low) will result in the most stable? what type of bonds have this?

Answer 18

low PE = most stable!
shared electrons between nonmetals (covalent bonds) have LOWER PE bc of interaction between both nuclei