2.4 - Electrons, bonding and structure Flashcards
Define the term ‘orbital’ ?
Orbital - A region of space about the nucleus holding up to 2 electrons with opposite spins
What are the different types of orbitals ?
s, p, d, f
What is the shape of s orbitals ?
Spherical
What is the shape of p orbitals ?
Dumbbell-shaped
What is the number of orbitals in the s, p, d and f sub-shells ?
- s = one orbital ( two electrons )
- p = three orbitals ( six electrons )
- d = five orbitals ( ten electrons )
- f = seven orbitals ( fourteen electrons )
Do you know how to write electron configuration of atoms and ions ?
Yes
What are the rules for how shells are occupied by electrons ?
- The orbitals fills from the lowest energy levels
- The 4s orbital fills up before the 3d orbital
- The 4s orbital loses electrons first before the 3d orbital
Do you know how to write electron configuration using boxes ?
- Electrons will prefer to occupy orbitals on their own unless that option is unavailable
- Yes…
What are the exceptions to the rules of electron configuration ?
- Chromium and Copper
- The 4s orbital is occupied by one electron and is not completed as the 3d orbital is filled
Write the electron configuration for chromium and copper ?
- Chromium = 1s² 2s² 2p⁶ 3s² 3p⁴ 4s¹3d⁵
- Copper = 1s² 2s² 2p⁶ 3s² 3p⁴ 4s¹ 3d¹⁰
Define the term ‘ionic bond’ ?
Ionic bond - The strong electrostatic attraction between oppositely charged ions
What is the structure of ionic compounds ?
- They have a Giant Ionic lattice structure
- Each ion is surrounded by oppositely charged ions held together by strong ionic bonds
- The regular cubic arrangement gives the crystal its cubic shape
Explain the structure of an ionic compound such as sodium chloride ( NaCl ) ?
- Each positive sodium ion is surrounded by six negative chlorine ions forming a giant ionic lattice
- The regular cubic arrangement gives the crystal its cubic shape
Draw a diagram representing the structure of an ionic compound ( eg. NaCl ) ?
What are the physical properties of ionic compounds ?
- High melting/ boiling point
- Only conducts electricity when molten/ solution
- Brittle
- Soluble in polar solvents ( eg. Water )