CHEM120-62398 Introduction to Organic and Biological Chemistry Ionic and Covalent Compounds

Chamberlain University

CHEM120-62398 Introduction to Organic and Biological Chemistry Ionic and Covalent Compounds

CHEM120: Week 2 lab
Name:
Laboratory 3: Ionic and Covalent Compounds
Learning Objectives:
● Name ionic and covalent compounds and derive their chemical formulas
● Observe absorption spectra of metal ions using flame test
● Draw Lewis structures of simple covalent compounds
In this laboratory exercise, we will learn how to derive formulas of ionic and covalent compounds and
name them. We will also flame test for various metal ions and make models of simple covalent molecules.
Notes:
● Read the lab before coming to class. The expectation at Chamberlain (CCN/CU) is that you come
to class fully prepared for lab.
● This lab will involve the use of acids and burners. Be careful and mindful of your surroundings
as you handle the chemicals and burners.
● Always check with your instructor regarding proper waste disposal
● Listen carefully to the professor’s instructions and work safely
● Always follow the rules outlined in the safety contract
● If in doubt of how to use a piece of lab equipment, as you instructor. Improper use of lab
equipment can be dangerous or could damage lab materials.
● If you have any safety concerns, see your instructor.
● Always dress properly for lab. Be sure to wear closed toed shoes and long pants to lab. In lab,
ware your safety equipment including goggles, lab coat, and gloves.
● Use deionized water (DI water) in your experiments.
Exploration 1: Explain the following terms (Complete prior to class).
Cation: A positive ion
Anion: A negative ion
Ionic bond: A bond between a nonmetal + metal
Polar covalent bond: A type of chemical bond where a pair of electrons is unequally shared
between two atoms
Nonpolar covalent bond: A type of chemical bond where two atoms share a pair of electrons
with each other.
Hydrogen bond: A weak bond between two molecules resulting from an electrostatic
attraction between a proton in one molecule and an electronegative atom in the other.
CHEM120: Week 2 lab
Name:
Exploration 2: Ionic compounds
Ionic compounds are hard, brittle and crystalline in nature. Ionic compounds have high melting points
compared to covalent compounds. Many Ionic compounds are water soluble and conduct electricity. It is
possible to identify a compound as an ionic compound or a covalent compound by observing properties
such as melting point, solubility and ability to conduct electricity. These properties are due to the nature
of the ionic bond.
Ionic compounds are made between oppositely charged ions- a cation and an anion. The cation may be a
positively charged polyatomic ion or a metal ion. The anion may be a negatively charged polyatomic ion
or a nonmetal ion. In this activity, we will learn about naming ionic compounds and deriving their
chemical formulas.
Part 2A: Cations and their names
Metals form cations by donating electrons in their valence shell to satisfy the octet rule. The name of a
cation is the same as name of the element. Complete Table 1 by providing names of cations, their
chemical symbols and charges.
Table 1:
Number Name of
Element
Chemical symbol
of the element
Name of the cation Chemical symbol and
charge of the cation
1 Lithium Li Lithium ion Li+
2 Calcium Ca Calcium ion Ca2+
3 Sodium Na Sodium ion Na+
4 Aluminum Al Aluminum ion Al3+
5 Barium Ba Barium ion Ba2+
6 Rubidium Rb Rubidium ion Rb+
7 Iron Fe2 Iron (II) Fe2+
8 Iron Fe3 Iron (III) Fe3+
9 Copper Cu1 Copper (I) Cu+
10 Copper Cu2 Copper (II) Cu2+
Part 2B: Anions and their Names
Non-metals form anions by accepting electrons to complete their valence shell and satisfy the octet rule.
The name of an anion is never the same as the name of the element, but rather is named by adding the
suffix – ide . Complete Table 2 by providing names of anions, their chemical symbols and charges.
Table 2:
Number Name of
Element
Chemical symbol
of the element
Name of the anion Chemical symbol and

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