U3 Lesson 1A Check for Understanding
Ionic vs. Covalent Bonds
Part ONE: Use the Electronegativity Chart to get the electronegativity values for this practice sheet
- Determine the type of element in each compound as either metal (M), nonmetal (NM) or metalloid (META) and classify the bond type as Ionic, Polar Covalent or Nonpolar Covalent, according to the type of atoms.
Identical NM’s Nonpolar Covalent
Different NM’s Polar covalent
M/NM Ionic
- Using the table of electro-negativities provided, calculate the difference in electronegativity and then classify the bond type as Ionic, Polar Covalent or Nonpolar Covalent according to the EN difference.
0 – 0.4 Nonpolar Covalent
0.41 – 1.69 Polar Covalent
> 1.70 Ionic
| Compound | Types of Atoms | Bond Type | EN Difference | Bond Type |
|---|---|---|---|---|
| SiS2 | META/NM | Ionic | 2.5 - 1.8 = .7 | Polar Covalent |
| NaCl | M/NM | Ionic | 2.1 | Ionic |
| NH3 | NM/NM | polar covalent | 3.0-2.1=0.9 | polar covalent |
| Li2O | M/NM | Ionic | 3.5-1.0=2.5 | Ionic |
| H2O | NM/NM | polar covalent | 3.5-2.1=.4 | polar covalent |
| Ca3N2 | M/NM | Ionic | 3.0-1.0=2.0 | Ionic |
| SO3 | NM/NM | polar covalent | 3.5-2.5=1.0 | polar covalent |
| H2 | NM/NM | nonpolar covalent | 2.1-2.1=0 | nonpolar covalent |
| CuF | M/NM | Ionic | 4.0-1.9=2.1 | Ionic |
| * CH4 | NM/NM | polar covalent | .4 | nonpolar covalent |
- Do most predictions of bond type using electronegativity match to the prediction of bond type using types of atom?
Yes
- What type of bond results from an electronegativity difference greater than 1.7 and consists of a metal and nonmetal?
Ionic
- What type of bond results from an electronegativity difference less than 1.7 and consists of only nonmetals?
polar covalent
- What type of bond must always result between a diatomic or triatomic molecule?
nonpolar covalent diatomic elements are the 7 on the periodic table ( nitrogen oxygen Cl etc) in n2, ionic polar covalent nonpolar covalent or metallic n2 is nonpolar covalent triatomic is like O3, which is also nonpolar covalent
Part TWO: Write the electron configuration for the following ions:
Ca2+ 1s2 2s2 2p6 3s2 3p6
P3- 1s2 2s2 2p6 3s2 3p6
Al3+ 1s2 2s2 2p6 3s2 3p4