FACTORS AFFECTING ELECTRON ATTRACTIONS

1. FACTORS AFFECTING ELECTRON ATTRACTIONS

2. FACTORS AFFECTING ELECTRON ATTRACTIONS • IN ORDER TO STUDY CHEMISTRY, IT IS ESSENTIAL TO UNDERSTAND WHY ONE ATOM MIGHT HOLD ITS ELECTRONS MORE TIGHTLY THAN ANOTHER ATOM.

3. FACTORS AFFECTING ELECTRON ATTRACTIONS • DURING THIS LESSON YOU WILL: • 1) Take notes from this presentation in your notebook, • 2) Complete the “Attraction for Electrons worksheet”.

4. FACTORS AFFECTING ELECTRON ATTRACTIONS • YOU WILL APPLY THIS KNOWLEDGE IN LATER DISCUSSIONS IN CHEMISTRY.

5. ATTRACTION FOR ELECTRONS • How a particle behaves is determined by its attraction for electrons

6. ATTRACTION FOR ELECTRONS • How a particle behaves is determined by its attraction for electrons e- METAL weak attraction Metals and non-metals behave differently because of differing attractions for electrons e- STRONG ATTRACTION NON-METAL

7. THE CHARGE OF THE NUCLEUS • REMEMBER: • THE NUCLEUS IS COMPOSED OF PROTONS AND NEUTRONS. • PROTONS HAVE A POSITIVE CHARGE. • NEUTRONS ARE NEUTRAL.

8. THE CHARGE OF THE NUCLEUS • REMEMBER: • THE NUCLEUS IS COMPOSED OF PROTONS AND NEUTRONS. • PROTONS HAVE A POSITIVE CHARGE. • NEUTRONS ARE NEUTRAL. • THEREFORE THE CHARGE OF THE NUCLEUS IS POSITIVE.

9. THE CHARGE OF THE ELECTRONS • REMEMBER: • THE NUCLEUS IS COMPOSED OF PROTONS AND NEUTRONS. • PROTONS HAVE A POSITIVE CHARGE. • NEUTRONS ARE NEUTRAL. • THEREFORE THE CHARGE OF THE NUCLEUS IS POSITIVE. • THE CHARGE OF THE ELECTRON IS NEGATIVE.

10. SKETCH A PICTURE OF A C-12 ATOM e- e- e- 6 p+ 6 n0 e- e- e-

11. ATTRACTION FOR ELECTRONS • is because of the electrostatic attraction between the positively charged nucleus and the negatively charged electrons.

12. ATTRACTION FOR ELECTRONS • is because of the electrostatic attraction between the positively charged nucleus and the negatively charged electrons. I like you. I like you, too. e- NUCLEUS

13. FACTORS AFFECTING THE ATTRACTION FOR ELECTRONS • The distance between the electron and the nucleus. • The farther away, the less the attraction.

14. FACTORS AFFECTING THE ATTRACTION FOR ELECTRONS • The distance between the electron and the nucleus. • The farther away, the less the attraction. e- NUCLEUS Long distance relationships are so difficult NUCLEUS e- An electron which is twice as far away has only one quarter the attraction.

15. FACTORS AFFECTING THE ATTRACTION FOR ELECTRONS • The distance between the electron and the nucleus. • The farther away, the less the attraction. • The number of protons in the nucleus • The more protons, the greater the attraction

16. FACTORS AFFECTING THE ATTRACTION FOR ELECTRONS • The distance between the electron and the nucleus. • The farther away, the less the attraction. • The number of protons in the nucleus • The more protons, the greater the attraction e- p+ p+ 4 protons have twice the attraction of 2 protons. p+ e- p+ p+ p+

17. FACTORS AFFECTING THE ATTRACTION FOR ELECTRONS • The distance between the electron and the nucleus. • The farther away, the less the attraction. • The number of protons in the nucleus • The more protons, the greater the attraction • The number of electons in the nucleus • The more electrons, the less the attraction.

18. FACTORS AFFECTING THE ATTRACTION FOR ELECTRONS • The distance between the electron and the nucleus. • The farther away, the less the attraction. • The number of protons in the nucleus • The more protons, the greater the attraction • The number of electons in the nucleus • The more electrons, the less the attraction. • Electrons are repelled by each other, therefore the more electrons make the electron cloud “crowded” and “unattractive” to the electrons.

19. FACTORS AFFECTING THE ATTRACTION FOR ELECTRONS • The distance between the electron and the nucleus. • The farther away, the less the attraction. • The number of protons in the nucleus • The more protons, the greater the attraction • The number of electons in the nucleus • The more electrons, the less the attraction. • Electrons are repelled by each other, therefore the more electrons make the electron cloud “crowded” and “unattractive” to the electrons. • The inside electrons repel the outside electrons which is known as the shielding effect.

20. e- FACTORS AFFECTING THE ATTRACTION FOR ELECTRONS Hey, move over. You’re crowding me. • The distance between the electron and the nucleus. • The farther away, the less the attraction. • The number of protons in the nucleus • The more protons, the greater the attraction • The number of electons in the nucleus • The more electrons, the less the attraction. • Electrons are repelled by each other, therefore the more electrons make the electron cloud “crowded” and “unattractive” to the electrons. • The inside electrons repel the outside electrons which is known as the shielding effect. Go away. This one is mine. All mine. You guys disgust me. e- e- NUCLEUS Electrons repel each other. e- Get your own nucleus.

21. FACTORS AFFECTING THE ATTRACTION FOR ELECTRONS IN SUMMARY: • The farther away, the less the attraction for an atom’s electrons. • The more protons, the greater the attraction for an atom’s electrons. • The more electrons, the less the attraction for an atom’s electrons. THESE FACTORS ARE IN ORDER OF IMPORTANCE. (The distance between the nucleus and electron is much more important than the number of electrons.)

22. WAYS OF MEASURING ELECTRON ATTRACTION There are three ways to measure an atom’s attraction for its electrons: • IONIZATION ENERGY • ELECTRON AFFINITY • ELECTRONEGATIVITY

23. IONIZATION ENERGY • IONIZATION ENERGY • THE ENERGY REQUIRED TO REMOVE ONE VALENCE ELCTRON

24. IONIZATION ENERGY • IONIZATION ENERGY • THE ENERGY REQUIRED TO REMOVE ONE VALENCE ELCTRON ionization energy e- Ionization energy “shows” how hard you must “pull” in order to remove one electron from the atom. The more the atom attracts its electrons, the higher the ionization energy.

25. ELECTRON AFFINITY • ELECTRON AFFINITY • THE ENERGY GIVEN OFF WHEN THE ATOM GAINS ONE ELECTRON

26. ELECTRON AFFINITY • ELECTRON AFFINITY • THE ENERGY GIVEN OFF WHEN THE ATOM GAINS ONE ELECTRON electron affinity e- Electron affinity shows how much energy the atom is willing to “pay” to get another electron. The more the atom attracts electrons, the higher the electron affinity.

27. ELECTRONEGATIVITY • ELECTRONEGATIVITY • THE ATTRACTION FOR SHARED ELECTRONS

28. ELECTRONEGATIVITY • ELECTRONEGATIVITY • THE ATTRACTION FOR SHARED ELECTRONS e- COVALENT BOND Electronegativity shows how strongly an atom attracts the electrons that it is sharing with another atom. The more the atom attracts electron, the higher the electronegativity.

29. ELECTRONEGATIVITY • Each of the ways of measuring electron attraction is important but the electronegativity is the most important to us. • Electronegativity is assigned to each element after considering its ionization energy, electron affinity, and several other factors. • Electronegativity is a relative measurement. • What does relative mean? • An atom with an electronegativity of 4 has twice the attraction for shared electrons as an atom with an electronegativity of 2. • Electronegativity is used to compare the “strength” of one atom to the “strength” of another.