Two molecules used in the polymer industry are...

Two molecules used in the polymer industry are azodicarbonamide and methyl cyanoacrylate. Their structures are Azodicarbonamide is used in forming polystyrene. When added to the molten plastic, it decomposes to nitrogen, carbon monoxide, and ammonia gases, which are captured as bubbles in the molten polymer. Methyl cyanoacrylate is the main ingredient in super glue. As the glue sets, methyl cyanoacrylate polymerizes across the carbon-carbon double bond. (See Chapter 22.) a. Complete the Lewis structures showing all lone pairs of electrons. b. Which hybrid orbitals are used by the carbon atoms in each molecule and the nitrogen atom in azodicarbonamide? c. How many $\pi$ bonds are present in each molecule? d. Give approximate values for the bond angles marked $a$ through $h$ in the above structures.

Two molecules used in the polymer industry are azodicarbonamide and methyl cyanoacrylate. Their structures are
Azodicarbonamide is used in forming polystyrene. When added to the molten plastic, it decomposes to nitrogen, carbon monoxide, and ammonia gases, which are captured as bubbles in the molten polymer. Methyl cyanoacrylate is the main ingredient in super glue. As the glue sets, methyl cyanoacrylate polymerizes across the carbon-carbon double bond. (See Chapter 22.)
a. Complete the Lewis structures showing all lone pairs of electrons.
b. Which hybrid orbitals are used by the carbon atoms in each molecule and the nitrogen atom in azodicarbonamide?
c. How many $\pi$ bonds are present in each molecule?
d. Give approximate values for the bond angles marked $a$ through $h$ in the above structures.

Key Concepts

Lewis Structures

Lewis structures are diagrams that represent the arrangement of atoms, bonds, and lone electron pairs in a molecule. They are essential for visualizing how electrons are distributed in a chemical species, which in turn helps in predicting reactivity, molecular geometry, and the locations of formal charges.

Hybrid Orbitals

Hybrid orbitals result from the mixing of atomic orbitals to form new orbitals that are equivalent in energy and are optimally arranged for bonding. The type of hybridization (such as sp, sp2, sp3, etc.) determines the geometry of the molecule and the directionality of its bonds, affecting both bond angles and overall molecular shape.

Pi Bonds

Pi bonds are a type of covalent bond that forms from the side-by-side overlap of p-orbitals, typically occurring in addition to sigma bonds in double and triple bonds. Counting pi bonds in a molecule is important for understanding the level of unsaturation, the rigidity of the structure, and potential sites for chemical reactions.

Bond Angles and Molecular Geometry

Bond angles refer to the angles between adjacent bonds around a central atom, largely governed by the repulsions between electron pairs as described by VSEPR theory. These angles provide key insights into the three-dimensional arrangement of atoms in a molecule, which in turn affects physical properties such as polarity, phase, and reactivity.

Transcript

00:07 On this problem, we have two molecules.

00:10 And the first thing that the problem is asking us is that we need to draw the complete lewis dot structure showing all on pairs.

00:23 So basically, remember that the complete lewis dot structure includes an opt -ed.

00:32 So what we're looking at is that each one of our elements that make up this compound have a complete update.

00:45 So how do we do it? so first, we're going to look at this.

00:49 So remember, complete octet means eight.

00:52 So we have one, two, three.

00:56 Each line is equivalent to two electrons.

00:59 So we need two electrons in here.

01:02 So the first thing that we're going to do is that we're going to put two electrons in this nitrogen.

01:11 And now that nitrogen is happy.

01:15 Happy means that has eight electrons around.

01:18 So let's look at this carbon.

01:20 So we have one, two, three, four.

01:23 This carbon is completely happy because it has eight electrons.

01:27 Now let's look at this hydrogen.

01:29 It has one, two, three, each one of the first.

01:32 Them is equivalent to two so it had six so we need to put another set in here now let's move to this electron this atom so it's exactly the same we need two more louisost two more electrons in here and in here we have two and three we need two more in here and let's look now at this one it has one two, three, and four.

02:05 So this one is complete.

02:07 And this oxygen has two, that is equivalent to four.

02:12 So we need two more.

02:15 And now we are completed with that structure.

02:20 Now let's move to the second one.

02:22 We're going to do exactly the same thing.

02:26 This carbon has two, three, four times two is completed.

02:30 This carbon has one, two, three, four is completed.

02:36 This carbon has one, two, three, four bonds is completed.

02:41 My nitrogen only has three, so now it's happy because it has eight.

02:48 Now this one, this carbon in here has one, two, three, four, so it's completely full.

02:55 And now my oxygen only has two, so i need to put two more in the there.