Module Four: Part B Dot Structures of Molecules Lab Name:________

Draw the Dot Structures for each of the molecules in Module 4 Part B. Use alternating colored pencils or pens to show the where the electrons were originally attached to the single atom. Then you may also show a covalent bond as a stick instead of a pair of electrons shared. You may also use your envelop of paper atoms.

1. Problem #1: NH₃ CH₄ H₂O₂ H₂O

(all single covalent bonds in #1)

Ammonia NH₃

Methane CH₄

Hydrogen Peroxide H₂O₂

Water H₂O

also try (not all single bonds) O₂ H₂ N₂

2. Problem #2: H₂SO₄ H₃PO₄ HClO₄ HClO₃

(all single covalent bonds in #2)

Hydrogen Sulfate (molecular); Surfuric Acid (aqueous) H₂SO₄

Hydrogen Phosphate (molecular); Phosphoric Acid (aqueous) H₃PO₄

Hydrogen Perchorate (molecular); Perchoric Acid (aqueous) HClO₄

Hydrogen Chlorate (molecular); Chloric Acid (aqueous) HClO₃

also try (all single bonds) H₂SO₃ H₃PO₃ HClO₂ HClO

3. Problem #3: H₂CO₃ HNO₃ HNO₂

(contains at least one double covalent bond in #3)

Hydrogen Carbonate (molecular); Carbonic Acid (aqueous) H₂CO₃

Hydrogen Nitrate (molecular); Nitric Acid (aqueous) HNO₃

Hydrogen Nitrite (molecular); Nitrous Acid (aqueous) HNO₂

4. Problem #4 CO₂ HCN CO SO₃ SO₂

(contains at least one double or triple covalent bond in #4)

Carbon Dioxide CO₂ Carbon Monoxide CO

Hydrogen Cyanide HCN

Sulfur Trioxide SO₃ Sulfur dioxide SO₂

5. Problem #5: HC₂H₃O₂ H₂C₂O₄ HCHO₂

(contains at least one double covalent bond in #5)

(bond carbons to carbon by single covalent bonds in the first two)

Hydrogen Acetate (molecular); Acetic Acid (aqueous) HC₂H₃O₂

Hydrogen Oxalate (molecular); Oxalic Acid (aqueous) H₂C₂O₄

(bond hydrogens to oxygen by single covalent bonds, and bond two oxygens to each carbon)

Hydrogen Formate (molecular); Formic Acid (aqueous) HCHO₂

(bond one hydrogen to oxygen, bond the other hydrogen to the carbon by single covalent bonds, and bond the two oxygens to the carbon)

6. Problem #6: C₂H₄ C₂H₂ C₃H₈ C₂H₆

Ethylene C₂H₄ Acetylene C₂H₂

Propane C₃H₈ Ethane C₂H₆

7. CH₂O CH₃COCH₃ CH₃CH₂OH

Formaldehyde CH₂O (both hydrogens are on the carbon)

Acetone CH₃COCH₃

(bond all three carbons by single bonds and bond the oxygen to the middle carbon)

Ethyl Alcohol CH₃CH₂OH (a hydrogen is attached to an oxygen (-OH group) to create an alcohol. The –OH can be attached to any carbon in a chain. In this example the –OH is attached to the end carbon)

8. CH₃OCH₃ CHONH₂ CH₃CH₂CH₂OH CH₃CHOHCH₃

Dimethyl Ether CH₃OCH₃ (oxygen separtates the carbons in the chain for ethers)

Methanamide CHONH₂ (oxygen, hydrogen, and amino group all attach to the carbon in amides)

n-propyl Alcohol CH₃CH₂CH₂OH (the -OH alcohol group is attached to the last carbon and all three carbons are attached by single bonds to make a three carbon chain)

Isopropyl alcohol CH₃CHOHCH₃ (the -OH alcohol group is attached to the second carbon in the three carbon chain)

9. CH₂NH₂COOH CH₃CHNH₂COOH (Amino acids)

(the -NH₂ amino group is always attached to the #2 carbon in an amino acid)

(the –COOH group is an organic acid group, both oxygens bonded to the carbon and the hydrogen to an oxygen)

Glycine CH₂NH₂COOH

Alanine CH₃CHNH₂COOH

10. CH₃COOCH₂CH₃ CHOOCH₃ (these are organic esters. The hydrogen in an organic acid (the –COOH group) is replaced by an alkyl group, which is -CH₂CH₃ (the ethyl group) in the first structure and – CH₃ (the methyl group) in the second structure.)

Ethyl Acetate CH₃COOCH₂CH₃

Methyl Formate CHOOCH₃