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CHM 112
Section 1

Homework Assignment #1
Due January 25, 2006 by 8:05 a.m.

The first portion of this assignment is concerned with nomenclature of ions we will encounter in the course. You should know the names, formulas, and charges of all of these ions from here on.

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A. Give chemical formulas for the following ions:

0) chlorite ion  ClO2

1) chlorate ion  ClO3

2) perchlorate ion  ClO4

3) chromate ion  CrO42–

4) dichromate ion  Cr2O72–

5) cyanate ion  OCN

6) thiocyanate ion  SCN

7) oxalate ion  C2O42–

8) hydrogen phosphate ion  HPO42–

9) dihydrogen phosphate ion  H2PO4

B. Write the names for the following ions (spelling counts!):

0) C2H3O2  acetate ion

1) CO32–  carbonate ion

2) HCO3  bicarbonate ion or hydrogen carbonate ion

3) CN  cyanide ion

4) NO2  nitrite ion

5) NO3  nitrate ion

6) MnO4  permanganate ion

7) PO43–  phosphate ion

8) SO32–  sulfite ion

9) SO42–  sulfate ion

C. The following questions concern periodic properties, which are key to understanding chemical reactivity. Answer:

0) For B, C, N, O, and F, which has the largest ionization energy? Briefly explain.

F: ionization energy increases as you go across to the right on the periodic table.

1) For B, C, N, O, and F, which has the largest radius? Briefly explain.

B: atomic radius decreases as you go across to the right on the periodic table.

2) For B, C, N, O, and F, which has the largest electron affinity? Briefly explain.

F: electron affinity increases as you go across to the right on the periodic table.

3) For B, C, N, O, and F, which has the largest electronegativity? Briefly explain.

F: electronegativity increases as you go across to the right on the periodic table.

4) For Na, K, Rb, and Cs, which has the largest ionization energy? Briefly explain.

Na: ionization energy decreases as you go down the periodic table.

5) For Na, K, Rb, and Cs, which has the largest radius? Briefly explain.

Cs: atomic radius increases as you go down the periodic table.

6) For Na, K, Rb, and Cs, which has the largest electron affinity? Briefly explain.

Na: electron affinity decreases as you go down the periodic table.

7) For Na, K, Rb, and Cs, which has the largest electronegativity? Briefly explain.

Na: electronegativity decreases as you go down the periodic table.

8) For F, Cl, Br, and I, which has the largest ionization energy? Briefly explain.

F: ionization energy decreases as you go down the periodic table.

9) For F, Cl, Br, and I, which has the largest radius? Briefly explain.

I: atomic radius increases as you go down the periodic table.

D. The following reactions can easily be balanced by inspection. Note that the phase of matter is given for all reactions. In CHM 112, keeping track of the phase of matter in reactions is important. Thus, in all reaction that you write for this class you must include the phase of matter for all components to get full credit. Do not use fractions as stoichiometric coefficients. Balance:

0) Cl2O5(g) + H2O(l)2 HClO3(aq)

1) V2O5(s) + 2 H2(g)V2O3(s) + 2 H2O(l)

2) 4 Al(s) + 3 O2(g)2 Al2O3(s)

3) TiCl4(l) + 2 H2O(l)TiO2(s) + 4 HCl(aq)

4) Sn(s) + 2 NaOH(aq)Na2SnO2(s) + H2(g)

5) PCl5(g) + 4 H2O(l)H3PO4(aq) + 5 HCl(aq)

6) CH3SH(g) + 3 O2(g)CO2(g) + SO2(g) + 2 H2O(l)

7) 3 Zn(OH)2(s) + 2 H3PO4(l)Zn3(PO4)2(s) + 6 H2O(l)

8) 3 CH3CH2OH(l) + PCl3(g)3 CH3CH2Cl(l) + H3PO3(s)

9) WO3(s) + 3 H2(g)W(s) + 3 H2O(l)