Ch.8 Chemical Composition

Question 1

how to calc average mass?

Answer 1

avg mass=total mass / number

Question 2

how much does 1 atomic mass unit weigh?

Answer 2

1 atomic mass unit (amu)=1.66 x10^-24 g

Question 3

from numbers to amu’s (mass of element)

Answer 3

multiply by atomic mass

Question 4

from amu’s (mass of element) to numbers

Answer 4

divide by the atomic mass

Question 5

what is avogardos number

Answer 5

1 mol= 6.022 x 10 ^23 particles

Question 6

what does the definition of the mole give us a

Answer 6

relationship between mass and number of atoms

Question 7

the mole is equal to the number of atoms in

Answer 7

12.01 grams of pure carbon

12.01 g C = 1 mol C atoms=6.022 x10^23 particles

Question 8

what is molar mass?

Answer 8

the mass in grams of one more of a substance

Question 9

molar mass is numerically equal to what?

Answer 9

mass in atomic mass units

Question 10

units of molar mass are

Answer 10

grams per mole

Question 11

from numbers to moles

Answer 11

divide by 6.022 x 10 ^23

Question 12

from mole to numbers

Answer 12

multiply by 6.022 x 10 ^23

Question 13

from moles to grams

Answer 13

multiply molar mass

Question 14

from grams to moles

Answer 14

divide by molar mass

Question 15

from numbers to moles divide by

Answer 15

avargados #

Question 16

from moles to numbers

Answer 16

multiply by avaragados #

Question 17

molar mass of a substance is the

Answer 17

grams per mole of its entities

Question 18

what is monatomic elements?

Answer 18

the molar mass is the same as the atomic mass in grams per mole

Question 19

empirical formula

Answer 19

the simplest formula for a compound that agrees with the elemental analysis

Question 20

what does empirical formula show?

Answer 20

it shows the lowest whole number of moles and gives the relative number of atoms of each elect present

Question 21

molecular formula

Answer 21

the formula of a compound as exists showing the actual number atoms of each element in a molecule of a compound

Question 22

the molecular formula is always an integer multiple of the empirical formula units:

Answer 22

molecular formula=(emperical formula)n

Question 23

what does molar mass equal?
formula wise

Answer 23

molar mass=n x empirical formula mass