CL 5- electrons and bonding

Question 1

orbital

definition

Answer 1

a region of space in an atom that can hold up to 2 electrons with opposite spins

Question 2

s- orbital

shape, no. of electrons

Answer 2

spherical, 2 electrons (with opposite spins)

Question 3

p-orbital

Answer 3

dumbell/lobe, 2 electrons (with opposite spins)

Question 4

how many p-orbitals to make p-subshell?

Answer 4

3 (6 electrons)

Question 5

how many d-orbitals to make d-subshell?

Answer 5

5 (10 electrons)

Question 6

how many f-orbitals to make f-subshell?

Answer 6

7 (14 electrons)

Question 7

what’s the rule for electron configuration with 3d/4s?

Answer 7

when making ions, electrons are lost from 4s level before 3d level

Question 8

two exceptions to 3d/4s rule

Answer 8

1. Cr= 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹ 3d⁵
2. Cu= 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹ 3d¹⁰

Question 9

ionic bonding

definition

Answer 9

the electrostatic attraction between positive and negatively charged ions

Question 10

why do ionic compounds have high melting and boiling points?

Answer 10

• strong electrostatic attraction between oppositely charged ions
• which require a large amount of energy to overcome

Question 11

why are ionic compounds soluble in water?

Answer 11

polar water molecules break down the lattice by attracting the ions and surrouding them

Question 12

ionic compound conductivity

Answer 12

as solids,
* don’t conduct electricity
* no mobile ions, fixed in place
when molten,
* do conduct electricity
* mobile ions

Question 13

covalent bonding

definition

Answer 13

strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms (non-metals)

Question 14

average bond enthalpy

definition and explain

Answer 14

measure of covalent bond strength
the larger the average bond enthalpy, the stronger the covalent bond and the more energy is required to break it

Question 15

dative covalent bonding

Answer 15

one atom provides both electrons for the shared pair