Review: Formulas and Mole Conversions

Go to the answer key.
  1. What is a cation? Give an example.
  2. Where are the nonmetals located on the periodic table?
  3. Fill in the chart.

    Symbol

    Name

    # of p+

    # of no

    # of e-

    atomic #

    atomic mass

     

    aluminum ion

    		         

    O-2

    		           
       

    27

    		 

    25

    		   
           

    10

    9

    		 
     

    mercury

    		         

  4. Name the following compounds. State whether they are formula units or molecules.
    a) Na2SO4   b) N2O4   c) MgCl2   d) KH2PO4   e) SiF4
    f) HNO2   g) Fe(NO3)3   h) NO2   i) MnCrO4   j) Co3(PO4)2
  5. Write the formula for the following compounds.
    a) carbonic acid   b) barium chlorate   c) tin (IV) nitride   d) hydrochloric acid
    e) cobalt (I) hydride   f) nitrogen triiodide   g) sulfur hexachloride   h) silver carbonate
  6. State whether each of the compounds listed in #5 are molecular or ionic.
  7. List the three types of representative particles.
  8. Name the eight (seven for Mr. Koppel's class) diatomic molecules.
  9. How many atoms are in 0.455 moles of lead?
  10. Find the number of moles in 1.33 x 1021 molecules of oxygen.
  11. What is the mass of 1 molecule of carbon tetrachloride?
  12. How many formula units are in 14.22 grams of iron (III) oxide?
  13. What is the volume (in L) of 3.72 moles of hydrogen gas at STP?
  14. What is the mass of 370 L of nitrogen gas at STP?
  15. What is the density of methane (CH4, natural gas) at STP?
  16. Which compound contains the most copper, by weight: CuO, CuS, or Cu2S or Cu3PO4?
  17. A compound is found to be 53.0% aluminum and 47.0% oxygen. Find its empirical formula.
  18. A 1.338 gram sample of a compound contains 0.366 grams of Na and 0.220 grams of N. The rest is oxygen. Find the empirical formula.
  19. Find the molar masses of the compounds in questions #4 f-j.
  20. Vitamin C is an organic compound (and Mr. Koppel's favorite vitamin) which contains carbon, hydrogen, and oxygen. Analysis of a sample shows that it is 40.9 % C, 4.58 % H, and 54.5 % O. Its molar mass is about 180 g/mole. Find the molecular formula.
  21. What is the mass, in kg, of 5.00 x 1026 atoms of lead?
  22. How many atoms of carbon has a man given his fianceé if the engagement ring has a 0.500 carat diamond? There are 200.0 mg in a carat.
Answers to select problems:
9) 2.74 x 1023 atoms   10) 2.21 x 10-3 moles   11) 2.55 x 10-22 g   12) 5.360 x 1022 form. units.   13) 83.3 L
14) 460 g   15) .7165 g/L   16) CuO w/79.89% Cu   17) Al2O3   18) NaNO3   19) f) 47.02 g/mole
g) 241.88 g/mol   h) 46.01 g/mol   i) 170.94 g/mol   j) 366.73 g/mol   20) C6H8O6   21) 172 kg
22) 5.01 x 1021 atoms

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