chem midterm

Question 1

pure substance

Answer 1

materials that are only one compound or element

Question 2

mixture

Answer 2

contains more that one substance (homo or heterogenuos)

Question 3

physical change

Answer 3

changes that occur without altering the identity (malting metal into a new form)

Question 4

chemical properties

Answer 4

we cannot measure without changing identity (flamability)

Question 5

energy

Answer 5

the ability to do work

Question 6

Exothermic change

Answer 6

releases heat energy

Question 7

Endothermic change

Answer 7

absorbs heat energy

Question 8

metric prefixes

Answer 8

tera
gige
mega
kilo
standard one
deci
centi
milli
micro
nano
pico

Question 9

sig fig rules

Answer 9

1. All nonzero digits are significant,
   and all zeros between nonzero digits are significant.
   2.If a decimal point is present, zeros to the right of the last
   nonzero digit are significant.
2. Zeros to the left of the nonzero numbers are never significant.

Question 10

atomic theory

Answer 10

theory that all matter is composed of atoms
atoms of each element are unique
atoms can join together in ratios
atoms can react and burn the atom is still an atom

Question 11

law of conservation

Answer 11

in chemical reactions matter is neithr created or destroyed (if you add one to another you just add each other)

Question 12

how to calculate Fahrenheit

Answer 12

9/5 c + 32

Question 13

how to calculate celcius

Answer 13

5/9(F-32)

Question 14

how to calculate Kelvin

Answer 14

C+273.15

Question 15

which was do groups/famalies go

Answer 15

down

Question 16

which way do periods go

Answer 16

across

Question 17

how to tell how many electrons

Answer 17

the top number above the symbol

Question 18

what side are the noble gases on

Answer 18

far right side

Question 19

plum pudding model

Answer 19

envisioned negative electrons spread
throughout a positively-charged material.(looks like plum pudding)

Question 20

protons

Answer 20

posative charge

Question 21

nuetron

Answer 21

nuetral no charge

Question 22

electron

Answer 22

negative charge

Question 23

atomic identity

Answer 23

The number of protons determines
the identity of the atom

Question 24

atomic number=

Answer 24

the number of protons and electrons in a neutral atom

Question 25

how to calculate mass number

Answer 25

protons+nutrons

Question 26

isotopes

Answer 26

Have the same atomic number, but different mass number

Question 27

daltons atomic theory

Answer 27

Atoms are indivisible particles.

Question 28

bohr model

Answer 28

Electrons orbit the nucleus like planets orbit the sun

Question 29

Quantum Model

Answer 29

Electrons move in waves in the electron cloud

Question 30

how are ions formed

Answer 30

atoms gain or lose electrons to from ions

Question 31

lower frequency=

Answer 31

long wave length

Question 32

when does energy increase on the electromagnetic spectrum

Answer 32

as it goes twoards the blue lights with high frequency and shorter waves

Question 33

wave length

Answer 33

the length of one wave

Question 34

frequency

Answer 34

the number of waves per second

Question 35

how to calculate energy

Answer 35

E=h(planks constant)v(frequency)

Question 36

whats line spectra

Answer 36

the idea that each element produces a unique line spectrum

Question 37

whats the photoelectric effect

Answer 37

light causes atoms to eject electrons

Question 38

where are lower energy electrons

Answer 38

towards the nucleaus

Question 39

sublevels

Answer 39

s p d f

Question 40

number of orbitals per sub level

Answer 40

s=1 p=3 d=5 f=7