1.†††††††† a.†††††††† 9.0g/mole

††††††††††† b.†††††††† 2*26.98+3*16.00;

††††††††††††††††††††††††††††††† 101.96g/mole

c.†††††††† >2*1.01;

†††††††††††††††††††††††††††††††† 2.02g/mole

d.†††††††† > 6*12.01+6*1.01;

††††††††††††††††††††††††††††††† 78.12g/mole

e.†††††††† > 2*12.01+4*1.01+2*16.00;

†††††††††††††††† †††††††††††††††60.06g/mole

f.††††††††† > 63.55+2*14.01+6*16.00;

††††††††††††††††††††††††††††††† 187.57g/mole

g.†††††††† > 131.3+195.09+6*19;

††††††††††††††††††††††††††††††† 440.39g/mole

2.†††††††† a.†††††††† 10g/(9.01*(g/mole));

†††††††††††††††††††††††††† 1.1 moles

b.†††††††††††††††††††† > 36g/(12.01*(g/mole));

††††† †††††††††††††††††††††3.0 moles

c.†††††††††††††††††††† > 0.105mole*(23.00+16.00+1.01)*(g/mole);

††††††††††††††††††††††††††††† 4.2 g

d.†††††††††††††††††††† > 1.0g/(18*(g/mole));

††††††††††††††††††††††††† 0.056 mole

e.†††††††††††††††††††† > 0.56g/(187.57*(g/mole));

††††††††††††††††††††††††† .002985552061 mole

f.††††††††††††††††††††† > 750g/(28*(g/mole));

†††††††††††††††††††††††††† 26.78571429 mole

3.†††††††† =120 moles *16 (g/mole) = 1920 g

4.†††††††† a.†††††††† 2

b.                  2

c.                   1

5.†††††††† 0.00010 = 1.0 X 10-4 mole

1.0  X 10-4 mole X 6.02 X 1023 atoms/mole = 6.02 X 1019 atoms.

6.†††††††† Carbon consists of a mixture of isotopes. 12.011 is the weighted average of those isotopesímasses.

7.†††††††† 0.2*g/(18*(g/mole))*(6.02*10^23)*(molecules/mole);

†††††††††††††††††††† = 6.67 x 1021 ††molecules

8.†††††††† Find the molar mass for each of the following:

a.†††††††† He

4.0 g/mole

b.†††††††† Fe2O3††

2(56)+3(16) = 160 g/mole

c.†††††††† O3† (ozone)

3(16) = 48 g/mole

d.†††††††† C5H5OH

5(12) +16 + 6(1) = 82 g/mole

e.†††††††† (NH4)2S

2(14) +8(1) + 32 = 68 g/mole

f.††††††††† Ca(NO3)2

40 + 2(14) + 6(16) = 164 g/mole

g.†††††††† Na2SO4

2(23) + 32 + 4(16) = 142 g/mole

9.†††††††† Convert the following:

a.†††††††† 30 grams of C = __?__ moles

30g (mole/12 g) = 2.5 moles

b.†††††††† 56 g of N= __?__ moles

56 g of N(mole/14 g) = 4.0 moles

c.†††††††† 0.356 moles of NaNO3 = __?__ grams

0.356 moles of NaNO3(23 + 14 + 3(16) g/mole) = 30.3 g

d.†††††††† One gram of H2O2 = __?__ moles

1g (mole/34 g) = 0.029 moles

e.†††††††† 100 g of Ca(NO3)2†††††† =__?__ grams

100 g of Ca(NO3)2(mole/164g) = 0.61 moles

f.††††††††† 0.750 g of O2 = __?__ moles

0.750 g of O2(mole/32g) = 0.023 moles

g.†††††††† One mole of copper= ___?___grams.

63.5 g

h.†††††††† 2.0 moles of sodium phosphate = ___?___ grams

2.0 moles Na3PO4(2*23 +31+4*16) = 328 g

i.††††††††† 2.58 g of potassium chloride = ___?___ moles

2.58 g KCl (mole/(39 + 35.5 g)) = 0.034 moles

10.†††††† What is the mass, in grams, of 12.0 moles of C3H8?

12 moles (44g/mole) = 528 g

11.†††††† What is the mass of a single molecule of He?

1† molecule(mole/6.02 X 1023 molecules)= 1.66 X10-24 moles

1.66 X10-24 moles* (4 g/mole) = 6.64 X 10-24 g