Year 11 Chemistry! Covalent Bonding Part A
1. Covalent Bonding By the end of this unit, you will be able to: 1. Define covalent bonding 2. Distinguish the different types of covalent bonds between atoms and molecules 3. Classify a range of covalent bonds into strong and weak 4. Determine the shape of molecules
1. Covalent Bonding - Activity
1. Covalent Bonding - Activity Q1. What do the people in the video represent? Q2. Describe two positive interactions between the people. Q3. Describe one negative interaction between the people. Q4. Name two people that seem socially withdrawn.
1. Covalent Bonding - Activity Q1. What do the people in the video represent? Different people represent different elements. Q2. Describe two positive interactions between the people. Carbon + Hydrogen and Sodium + Chlorine Q3. Describe one negative interaction between the people. Potassium + Water. not really negative, but explosive. Q4. Name two people that seem socially withdrawn. Helium and Neon
1. Covalent Bonding - Intro Covalent Bonding is most common bond found in nature by far It holds atoms, simple and very complex molecules together (non-metals) But why do atoms bond?
1. Covalent Bonding - Intro Like you and me, elements have a strong desire to become stable Stability = filled up outer shell Example: Oxygen has e- configuration of 1s 2 2s 2 2p 4, it wants to achieve a 1s 2 2s 2 2p 6 configuration.
1. Covalent Bonding - Intro
1. Covalent Bonding - Intro
1. Covalent Bonding - Intro The octet rule states that elements gain or lose electrons to attain an electron configuration of the nearest noble gas. Octet = set of 8, in this case a set of 8 electrons in the outer shell.
!!! 1. Covalent Bonding - Introduction Examples:! Oxygen and Sulfur: desperately need 2 electrons to become stable (they have 6 e - in the outer shell).! Fluorine and Chlorine: in despair for 1 electron (they have 7 e - in the outer shell).! Therefore, they need to capture electrons by any means!
1. Covalent Bonding - Intro 2 please!
1. Covalent Bonding - Intro 1 now!
1. Covalent Bonding - Intro It should be clear by now that some elements are not happy about themselves (their state) They bond to achieve stability = they form Covalent Bonds
Questions??
1. Covalent Bonding - Activity 2 Complete Activity 2 in your booklet
Year 11 Chemistry! Covalent Bonding Part B
2. Bonding - The Pretend Game The simplest molecule is formed when hydrogen atoms bond. (Fig. is 113pp) Important: outer shell electrons bond, forming pairs.
2. Bonding - The Pretend Game So for hydrogen, Covalent Bonding is like two people sharing a pair of pants.
2. Bonding - The Pretend Game The more complex molecules require more atoms to bond with! Complexity is related to the number of electrons an element craves for.
2. Bonding - The Pretend Game Examples: Single Bond, Chlorine gas (114 pp)
7 electrons! I need one more!
The Pretend Game Two Chlorine atoms decide to share the 7th electron of their outer shells.
The Pretend Game Two Chlorine atoms decide to share the 7th electron of their outer shells.
The Pretend Game We simplify the visualisation of the bond by only drawing the electrons located in the outer shell (114 pp).
The Pretend Game
The Pretend Game Chlorine gas (Cl2)
Questions??
3. Covalent Bonding - Activity 3 The Identity Game! You will be given a new identity. Now, it is your task to find someone to become stable with. Remember: 1.) You can bond with anybody as long as your final electron count = 8 (Octet Rule)
3. Covalent Bonding - Activity 3 The Identity Game Which element was the easiest and the hardest to achieve stability?, Why? Easiest Why? Hardest Why?
3. Covalent Bonding - Activity 3 Q8. Which element can benefit from Covalent Bonding to form very complex molecules? a) Carbon b) Nitrogen c) Oxygen d) Chlorine e) Astatine
3. Covalent Bonding - Activity 3 Q8. Which element can benefit from Covalent Bonding to form very complex molecules? a) Carbon b) Nitrogen c) Oxygen d) Chlorine e) Astatine
Eight allotropes of carbon: a) diamond b) graphite c) lonsdaleite d) C60 buckminsterfullerene e) C540, Fullerite f) C70 g) amorphous carbon h) single-walled carbon nanotube.
3.1. Increasing complexity Also important: Charge cloud diagrams are more realistic pictures of how molecules bond (Figure 7.8).
3.1. Increasing complexity Also important: Charge cloud diagrams are more realistic pictures of how molecules bond (Figure 7.8).
3.1. Increasing complexity Also important: Charge cloud diagrams are more realistic pictures of how molecules bond (Figure 7.8).
3.1. Increasing complexity How many bonds (aka, pairs)?
3.1. Increasing complexity How many bonds (aka, pairs)?
3.2. Double and triple bonds Some molecules have double and triple covalent bonding Remember: 1 Covalent Bond = sharing of 1 pair of electrons example: O2 and N2 gas have respectively 2 and 3 pairs shared in one go!
3.2. Double and triple bonds Now, imagine that you have to break the O2 and N2 bonds. Which bond would be harder to break?
3.2. Double and triple bonds Now, imagine that you have to break the O2 and N2 bonds. Which bond would be harder to break?