Example 2.12: Predicting the Type of Bonding in Compounds
Predict whether the following compounds are ionic or molecular. For ionic compounds, show the dissociation equation:
(a)
\(\ce{KI}\), the compound used as a source of iodine in table salt
(b)
\(\ce{H2O2}\), the bleach and disinfectant hydrogen peroxide
(c)
\(\ce{CHCl3}\), the anesthetic chloroform
(d)
\(\ce{Li2CO3}\), a source of lithium in antidepressants
Solution
(a) Potassium (group
1) is a metal, and iodine (group
17) is a nonmetal;
\(\ce{KI}\) is predicted to be ionic.
(b) Hydrogen (group
1) is a nonmetal, and oxygen (group
16) is a nonmetal;
\(\ce{H2O2}\) is predicted to be molecular.
(c) Carbon (group
14) is a nonmetal, hydrogen (group
1) is a nonmetal, and chlorine (group
17) is a nonmetal;
\(\ce{CHCl3}\) is predicted to be molecular.
(d) Lithium (group
1) is a metal, and carbonate is a polyatomic ion;
\(\ce{Li2CO3}\) is predicted to be ionic.
[a]
\(\ce{KI}\)\(\ce{->}\)\(\ce{K+}\)\(\ce{ + }\)\(\ce{I-}\)\(\ce{ }\)
[d]
\(\ce{Li2CO3}\)\(\ce{->}\)\(\ce{2 Li+}\)\(\ce{ + }\)\(\ce{CO3^2-}\)\(\ce{ }\)