CHAPTER 5 Problems
1) Write Lewis dot symbols for the following atoms:
a) Ca b) Se c) B d) Cl e) He
2) Write Lewis dot symbols for the following ions:
a) Li+ b) Cl- c) S2- d) Sr2+ e) N33) (Burdge, 5.10) Explain what ionic bonding is.
4) Specify which compound in each of the following pairs of ionic compounds should
have a higher lattice energy. Explain your choice.
a) AlN or CaO, b) NaF or CsF, c) MgCl2 or MgF2
5) Give the empirical formula and name for the compounds formed from each of the pairs
of ions: a) Rb+ and I-, b) Cs+ and SO42-, c) Sr2+ and N3-, d) Al3+ and S26) (Burdge, 5.98) Predict the formula and name of the binary compound formed from the
following elements:
a) Na and H, b) B and O, c) Na and S, d) Al and F, e) F and O, f) Sr and Cl
7) (Burdge, 5.33) Two different compounds, each containing only phosphorus and
chlorine, were decomposed into their constituent elements. One produced 0.2912 g P for
every gram of Cl; the other produced 0.1747 g P for every gram of Cl. Show that these
results are consistent with the law of multiple proportions.
8) (Burdge, 5.38) Define molecular formula and empirical formula. What are the
similarities and differences between the empirical formula and the molecular formula of a
compound?
9) (Burdge, 5.65) Explain the difference between the terms molecular mass and formula
mass. To what type of compound does each refer?
10) (Burdge, 5.48) Write the molecular formula of ethanol from the model shown. The
color codes are black (carbon), red (oxygen), and white (hydrogen).
11) (Burdge, 5.46) Write the empirical formulas of the following compounds:
a) Al2Br6, b) Na2S2O4, c) N2O5, d) K2Cr2O7
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12) Write the empirical formulas for the following organic compounds:
a) C6H6, b) CH3CH2CH3, c) CH3COOH, d) CH3CH2C(CH3)3
13) (Burdge, 5.68 a, b, e) Calculate the molecular mass or formula mass (in amu) for each
of the following substances: a) Li2CO3, b) C2H6, e) Fe(NO3)3
14) Find the percent composition for copper (II) nitrate (Cu(NO3)2).
15) (Burdge, 5.74) For many years chloroform (CHCl 3) was used as an inhalation
anesthetic in spite of the fact that it is also a toxic substance that may cause severe liver,
kidney, and heart damage. Calculate the percent composition by mass of this compound.
16) If we know the empirical formula for a compound, what additional information do we
need to determine its molecular formula?
17) Determine the empirical formulas for the compounds with the following
compositions: a) 2.1 % H; 65.3 % O; 32.6 % S, b) 20.2 % Al; 79.8 % Cl
18) The empirical formula of a compound is CH. If the molar mass of this compound is
about 78 g, what is its molecular formula?
19) How many moles of substance are contained in 100.0 g of the following compounds:
a) NaCl, b) CHCl3
20) (Burdge, 5.84) How many molecules of ethane (C 2H6) are present in 0.334 g of
ethane?
21) Ascorbic acid (vitamin C) contains C, H, and O. In one analysis, a sample of
ascorbic acid was found to contain 2.145 g carbon, 0.239 g hydrogen, and 2.86 g oxygen.
No other elements were present. Find the empirical formula and for ascorbic acid.
22) Monosodium glutamate (MSG), a food flavoring enhancer, has been blamed for
“Chinese restaurant syndrome”, the symptoms of which are headache and chest pains.
MSG has the following composition by mass: 35.51 percent C; 4.77 percent H; 37.85
percent O; 8.29 percent N; and 13.60 percent Na. What is its molecular formula if its
mass is about 169 g?
23) (Burdge, 5.55) Name the following binary molecular compounds:
a) NCl3, b) IF7, c) P4O6, d) S2Cl2
24) (Burdge, 5.61) Name the following compounds: a) KClO, b) Ag2CO3, c) HNO2,
d) KMnO4, e) CsClO3, f) KNH4SO4, g) Fe(BrO4)2, h) K2HPO4
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25) (Burdge, 5.63) Write formulas for the following compounds: a) copper (I) cyanide,
b) strontium chlorite, c) perbromic acid, d) hydroiodic acid, e) disodium ammonium
phosphate, f) lead (II) carbonate, g) tin (II) sulfite, h) cadmium thiosulfate
26) What is wrong with the name for each of the following compounds:
a) BaCl2 (barium dichloride), b) Fe2O3 (iron (II) oxide), c) CsNO2 (cesium
nitrate), d) Mg(HCO3)2 (magnesium (II) bicarbonate)
27) Fill in the blanks in the table.
Cation
Anion
Formula
Name
Magnesium bicarbonate
SrCl2
Fe
3+
-
NO3
Manganese (II) chlorate
SnBr4
Co2+
Hg22+
PO43ICu2CO3
Lithium nitride
Al
3+
2-
S
3