Chapter 3Chapter 3

Chemical Quantities

(The Mole)

The MoleThe Mole1 dozen =1 gross = 1 ream =

1 mole =

121445006.02 x 1023

1 mole Carbon = 12.01 g Carbon

6

C12.01

1 mole Carbon = 6.02 x 1023 atoms C

Molar Mass

Molar MassMolar MassThe mass in grams of 1 mole of a substance.

1

H1.01

1 mole H = 1.01 g H

Calculating Molar MassCalculating Molar MassAmmonium ChlorideAmmonium Chloride

+ 35.45 g =+ 35.45 g = 53.50 g53.50 g

NHNH44ClCl

14.01 g14.01 gx 1x 1

1.01 g1.01 gx 4x 4

14.01 g14.01 g + 4.04 g+ 4.04 g

35.45 g35.45 gx 1x 1

7

N14.01

1

H1.01

17

Cl35.45

Calculating Molar MassCalculating Molar MassAluminum nitrateAluminum nitrate

+ 48.00 g) =

= 213.01 g= 213.01 g

Al(NOAl(NO33))33

26.98 gx 1

14.01 gx 1

26.98 g

(14.01 g

16.00 gx 3

x 362.01

26.98 g

+ 186.03

13

Al26.98

7

N14.01

8

O16.00

Alternate methodAlternate methodAluminum nitrateAluminum nitrate

+ 144.00 g =213.01 g

Al(NOAl(NO33))33

26.98 gx 1

14.01 gx 3

26.98 g

+ 42.03 g

16.00 gx 9

13

Al26.98

7

N14.01

8

O16.00

20

Ca40.08

8

O16.00

1

H1.01

Calculating Molar MassCalculating Molar MassCalcium hydroxideCalcium hydroxide

= 74.1 g = 74.10 g

Ca(OH)Ca(OH)

40.08 gx 1x 1

16.00 g

40.08 g

+ 1.01 g

x 217.01

40.08 g

+ 34.02

2

12

Mg24.31

15

P30.97

8

O16.00

Calculating Molar MassCalculating Molar MassMagnesium Magnesium phosphatephosphate

+ 64.00 g) =

= 262.87 g

MgMg33(PO(PO44))22

24.31 g24.31 gx 3x 3

30.97 gx 1

72.93 g

(30.97 g

16.00 gx 4

x 294.97

72.93 g

+ 189.94

12

Mg24.31

15

P30.97

8

O16.00

Calculating Molar MassCalculating Molar MassMagnesium Magnesium phosphatephosphate

+ 128.00 g =262.87 g

MgMg33(PO(PO44))22

24.31 g24.31 gx 3x 3

30.97 gx 2

72.93 g

+ 61.94 g

16.00 gx 8

Calculating Molar MassCalculating Molar MassDinitrogen tetroxideDinitrogen tetroxide

92.02 g

NN22OO44

14.01 gx 2

16.00 gx 4

28.02 g + 64.00 g =

7

N14.01

8

O16.00

Calculating Molar MassCalculating Molar MassPhosphorus pentachloridePhosphorus pentachloride

208.22 g

PClPCl55

30.97 gx 1

35.45 gx 5

30.97 g + 177.25 g =

15

P30.97

17

Cl35.45

Calculating Molar MassCalculating Molar MassNitrogen monoxideNitrogen monoxide

= 30.01 g

NONO

14.01 g + 16.00 g

7

N14.01

8

O16.00

Calculating Molar MassCalculating Molar MassCarbon tetrachlorideCarbon tetrachloride

153.81 g

CClCCl44

12.01 gx 1

35.45 gx 4

12.01 g + 141.80 g =

6

C12.01

17

Cl35.45

Molar MassMolar Mass = Mass of 1 mole.

Type of compound Units Meaning

Ionic Compound(Cation + anion)

(metal w/ nonmetals)gfm gram formula

mass

Molecular Compounds(nonmetal groupings) gmm gram molecular

mass

Atoms(elements by themselves)

gam gram atomic mass

Molar Mass (general meaning) g/mol grams/mole