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LECTURE 1: LATTICE ENERGY, ELECTRON AFFINITY AND BORN HABER CYCLE

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You can try again the quizizz until 8pm on 27/7/21

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Join an activity with your class and find or create your own quizzes and flashcards.

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very clear explanation about the concept and very well paced with clear examples.

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In this lecture, i learned:

1) the definition of lattice energy (always exothermic) + the factors affecting lattice energy (charge density = charge/volume, the higher the charge density the more negative the value)

2) the definition of standard enthalpy change of atomisation (always endothermic) + the bond energy in the data booklet is for 2 atoms, bond energy divided by 2 is the standard enthalpy change of atomisation.

3) the definition of 1st ionisation energy (1st and so on is always endothermic) + the trend of 1st ionisation energy across the period & down the group in the periodic table (increase across the period and decreases going down the group)

4) the definition of first electron affinity (1st is always exothermic, 2nd and so on is always endothermic) + the trend of first electron affinity across the period for non metals (across the period the charge increases)  + the trend of first electron affinity down the group 15,16,17 (down the group the volume increases)

5) the definition of standard enthalpy change of formation (can be exo/endothermic)

6) how to make use of the Born-Haber cycle.

I still have trouble understanding why the first electron affinity is exothermic while the second and onwards are endothermic.

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We have learnt about the Born-Haber cycle, lattice energy, charge density and electron affinity. Clear and thorough explanations.

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i love how it refreshes my memory about enthalpy change of electron affinity, lattice energy, atomisation and formation.

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We have learnt about lattice energy and how to draw the Born-Haber Cycle. We also learnt the factors that affect lattice energy    . We learnt that lattice energy is always exothermic. I think the lessons was very informative and it helped me review and understand the lessons better.

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Today, we reviewed about Lattice energy and how to find it by drawing the Born-Haber Cycle. We learnt that Lattice energy is always exothermic. We also learnt about the Electron affinity and Ionization Energy as well as it's trends. Overall, it was a great review to our new topic that we learnt during the first week.

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Learnt about:
- Lattice energy is always exothermic
-  Electron affinity can be both negative and positive, 1st electron affinity is exothermic while 2nd and 3rd electron affinity is normally endothermic.
- Electron affinity decreases along the group and increases down the period.
- How to draw Born-Haber cycle
- Born-Haber cycle is used to calculate lattice energy

I still need to review on the reasonings behind all the trends and try to be able to produce an answer instinctively as sometimes i still get confused

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Today we reviewed about the definitions of lattice energy, enthalphy change of atomisation,   1rst ionization energy and electron affinity. We also reviewed the trend and the properties of these topics and also learnt how to calculate the born haber cycle diagram .
The lecture detailed revision about the chapter. It was clear and straight to the point. However the  drawing the Born Haber cycle is still quite difficult for me

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We have learned about:
- The enthalpy changes of atomization, ionization energy, electron affinity, lattice energy and formation.
- The trends and reasoning behind the Electron Affinity, Lattice Energy and others, including how the charge density and the factors that affect it is responsible for the trends in Electron Affinity and Lattice Energy.
- How to draw the Born-Haber Cycle and how to use it.

I am still memorizing the trends and reasoning behind the trends, as it can get a little confusing.

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Review on:
1. Lattice energy
2. Enthalpy changes of atomization and solution
3. Electron Affinity
4. Charge Density
5. Born-Haber Cycle

Learnt that:
-Lattice energy is always exothermic because it is bond forming
-Ionization energy is always endothermic as it breaks bond
-Factors that affect the lattice energy, which are the size of the ion and the ionic charge

Overall, the lecture was very good as it was explained in a detailed and quick manner. I was able to understand it quite  easily and have a better understanding on this topic.

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The teacher did a thorough yet clear explanation on:
1. The enthalpy reactions: Atomisation, lattice, etc.
2. Electron affinity
3.Trends of the IE and EA both going across and down the group.
4. Born-Haber cycle, which was drawn simple so it was easy to understand.
5. Charge density.

Overall it was quite an enjoyable lesson, very clear and straight-to-the-point.

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Reviewed about lattice energy, enthalpy changes which are: atomisation and solution and finally electron affinity. Sir Gopi also reviewed about the trends of IE and EA going across and down the group for group 11 and 17. There was also a very simple diagram of the born haber cycle which is very easy to understand. Sir gopi marvelously explained that the charge density is essentially the reason for the amount of lattice energy. Sir Gopi also briefly explained why the 1st EA is always negative and why the 2nd and so forth EA is always positive. Overall, the lecture was a good review and I would partake in the lecture again.

I still need to differentiate faster between EA, IE and LE regarding the factors and trends

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Reviewed about

Lattice energy (examples equations trend and definition)
Enthalpy change
Electron affinity (as well as second and third electron affinity)
Born haber cycle

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I have learnt about the trends in ionization energy and electron affinity across and down the periodic table.
I have learnt how to draw and understand the Born Haber Cycle and the enthalpy change required.
I have learnt examples of lattice energy and the factors affecting it.

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1. The reason why the 1st EA going down group 15 16 17 becomes less negative              2.   Lattice energy is always exothermic(bond forming)          3. 1st EA is endothermic, 2nd and 3rd EA are exothermic.

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Review on lattice energy and electron affinity. Trend of electron affinity across period (more negative)  and down the group (less negative). Explanation on how to draw a Born Haber cycle. Factors that affect lattice energy: ion size and ionic charge.
Overall the lecture was very detailed, especially with the usage of checkpoints. I still need to further learn on how to draw a Born Haber cycle.

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Learnt :
Lattice energy - always exothermic
Ionization energy - always endothermic, across the period increases, down the group decreases
Electron affinity - 1st —> exothermic, 2nd,3rd —> endothermic
Enthalpy change of atomization
Factors affecting lattice energy - size of ion, ionic charge
Born haber cycle - clockwise = anticlockwise

It was a pretty quick, but very detailed revision about the chapter. I still need to get used to drawing the Born Haber cycle

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Very good

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Review about :
- Atomisation
- Lattice energy :
1. Always exo
- IE :
1.Always endo because break bond
2. Going across the periodic table : Increase , because it is held more strongly to the nucleus, harder to remove so more energy is needed
3. Going down the periodic table : decrease , because shielding effect increase, distance increase , outweigh increase in protons
- Electron Affinity :
1. 2nd and 3rd Ea : endo, because electrons repel electrons
2. Trend of Ea :
* Going across : more negative
* Going down : less negative
- How to draw Born- Haber cycle
1.  Clockwise = anticlockwise
- Factor effect lattice energy :
1. Smaller ionic size
2. Greater ionic charge

Learn :
- If Cl-Cl have a bond energy of 244kJ need to divide by 2 for enthalpy change of atomization

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Really good teaching method. I was able to understand a lot of things

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an understandable and clear explanation about charge density, Haber-Born cycle and enthalpy changes

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We were re-introduced to the definition of lattice energy and that it is mainly affected by its ionic charge (smaller charge, decreases; larger charge; increases). We reviewed the lattice energy equations of NaO, MgBr2 and MgS, the definitions of atomisation, ionisation enerrgy and electron affinity and re-emphasised the importance of the states of matter of Cl2(g), Br(l) and I2(s). I have not fully grasped the trends of ionisation energies and electron affinities and still struggle to draw Born Haber diagrams; I will look to the textbook's new version as advised.

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Very clear explanation about the concept, well organized, well paced, clear examples.

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best teaching i've ever experience, the explanations are clear and i can understand the examples

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best teaching i've ever experience, the explanations are clear and i can understand the examples

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amazing.

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The lecture is entertaining and clear

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Sir you are very impressive 🤩-Josh

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I love you sir Gopi tqqq

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The explanations were clear and the the example questions was really helped us understand the topic deeper.

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The explanations were clear and the the example questions was really helped us understand the topic deeper.

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Have more idea about the topic.

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Very clear voice and good explanation

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The explanations were quite clear and I think I have a better understanding of the trends across a period and down a group :)

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very clear explanations, very comprehensive.

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very clear explanations, very comprehensive.

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Very nice lecture, the method of teaching is amazing.

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Very nice lecture, the method of teaching is amazing.

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Today's lecture was a success! The lesson was very clear and I learnt a lot today.

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Today's lecture was a success! The lesson was very clear and I learnt a lot today.

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The explanation was very detailed and clear. Perfect learning pace especially with the inclusion of checkpoints and great examples.

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The explanation was very detailed and clear. Perfect learning pace especially with the inclusion of checkpoints and great examples.

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I really enjoyed today's lecture, the examples were very clear and easy to follow. Thank you so much

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I really enjoyed today's lecture, the examples were very clear and easy to follow. Thank you so much

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I have learnt about definitions and how to draw a Born-Haber cycle. I am still having doubts on the trends of electron affinity but I will look at it again using the notes.