SCH3U     Atomic Weights & Masses         Answers
State the full meaning of the following:

a)    Fe        b)    CuCl2        c)    2 Ca        d)    4 Fe2(SO4)3
2. How many atoms of hydrogen are represented in each of the following molecules?

a)    KHCO3    b)    H2SO4    c)    C3H   d)    HC2H3O2    e)    (NH4)2SO4    f)    (CH3)3COH
3. Asbestos, a known cancer-causing agent, has a typical formula, Ca3Mg5(Si4O11)2(OH)2.  How many atoms of each element are given in the formula?
4. How many atoms of each kind are represented in the following formulas?

a)    Na3PO4          b)    Ca(H2PO4)       c)    C4H10

        d)    Fe3(AsO4)   e)    Cu(NO3)2            f)   MgSO4•7H2O
5. How many atoms of each element are represented in the formula of cobalt(II) chloride hexahydrate?

6. Calculate the molecular weight (mass) of H3PO4 and HClO4.
7. Calculate the molecular masses of:

a)   SO2     b)   P4O10        c)   UF6         d)   NH        e)   CCl4
8. Determine the molecular mass of these compounds:

a) methane, CH4                                        b)  potassium perchlorate, KClO4

c) phosphorus trichloride, PCl                  d)  sulphuric acid, H2SO4

e) silicon dioxide, SiO2                               f)  nitrogen(IV) oxide, NO2

g) nitrogen(V) oxide, N2O5                         h)  glucose, C6H12O6
9. What is the molecular weight of each of these common chemicals compounds?

a)   sodium bicarbonate, NaHCO3                  b)   laughing gas, N2O

c)   Potassium permanganate, KMnO4         d)    limestone, CaCO3

e)   Epsom salts, MgSO4•7H2O                    f)    ozone, O3