From atoms to molecules

Question 1

Valence electron

Answer 1

• Electrons an atom must lose or gain to attain the nearest noble gas

Question 2

Atomic orbitals

Answer 2

Grouped into different “shells” at different distances from the nucleus

Question 3

Quantum number

Answer 3

Each shell can contain up to 2n^2 electrons, where n is the number of the shell

Question 4

Molarity

Answer 4

number of moles of solute per liter of solution unit of molarity is mol/l or M

Question 5

Molecular weight

Answer 5

Mass of a molecule of a substance. The units are atomic mass units (amu).

Question 6

Molar mass

Answer 6

Mass of one mole of a substance in grams per mole or g/mol.

Question 7

Exceptions for the octet rule transition metals

Answer 7

• Cr electron configuration of [Ar]4s2 3d4 however theres an electron promotion so Cr is [Ar]4s1 3d5.
• Cu electron configuration is [Ar]4s13d10. It is more stable to move the electron from the 4s orbital into the 3d orbital fill d subshell

Question 8

Electronegativity

Answer 8

• Ability for an atom to attract electrons to itself

Question 9

Electronegativity

Ionic bonding

Answer 9

form when electronegativity difference between 2 atoms is > 1.7

Question 10

Electronegativity

Covalent bonding

Answer 10

form when electronegativity difference between 2 atoms is < 1.7

Question 11

Dipole-dipole interactions

Answer 11

Interactions between the positive end of one dipole and the negative end of another dipole

Question 12

Van der Waals Forces

Answer 12

Weak forces of attraction that exist between nonpolar molecules

Question 13

Hydrogen bonding

Answer 13

Attractive force between the H attached to an electronegative atom of one molecule and an electronegative atom

Question 14

Hybridisation effect

Answer 14

• 4 sp3 orbitals in a single bond
• 3 sp2 orbitals and 1 p orbital double bond
• 2 sp orbitals and 2 p orbitals triple bond
• s orbital for just hydrogen