Atomic and Quantum Theory
Which subatomic particle has a positive charge and determines the identity of an element?
Proton
Excluding the noble gases, which specific element on the periodic table has the highest electronegativity?
Flourine
What type of intermolecular forces are the weakest and exist between all molecules, including nonpolar ones?
dispersion forces
What are the electrons in the outermost shell of an atom called that are directly involved in forming chemical bonds?
Valence electrons
If a molecule is perfectly symmetrical and all individual bond dipoles cancel each other out completely, is the overall molecule polar or nonpolar?
Nonpolar
An uncharged isotope of Carbon has an atomic number of 6 and a mass number of 14. How many neutrons does it have?
8
If a neutral Calcium atom loses 2 valence electrons, what is the exact charge of the resulting cation?
+2
According to VSEPR theory, what is the molecular geometry of a methane molecule (CH4), which has four bonding pairs and zero lone pairs?
Tetrahedral
According to the octet rule, most main-group elements tend to react and form structures until they are surrounded by how many valence electrons?
8
Because Oxygen is significantly more electronegative than Hydrogen, which element holds a partial negative charge (δ−) in a polar water molecule?
oxygen
According to the quantum mechanical model, what is the name for the region of space around a nucleus where there is a high probability of finding an electron?
Orbital
What type of chemical bond involves the unequal sharing of electrons between two nonmetal atoms?
Polar covalent bond
A molecule like water (H2O) has 2 bonding pairs and 2 lone pairs on its central atom. What is its molecular geometry?
Bent
When drawing a Lewis structure, if the central atom still lacks an octet after assigning all single bonds and lone pairs, what type of bonds must you form by shifting lone pairs?
Multiple bonds
What is the term for the vector arrow used by chemists to point from the less electronegative atom toward the more electronegative atom, indicating a separation of charge?
Dipole moment (or Bond dipole)
When an electron absorbs energy, it jumps to an excited state. What is the term for the lowest, most stable energy level that the electron returns to?
Ground State
As you move from left to right across a period on the periodic table, does the atomic radius generally increase or decrease?
Decrease
Water (H2O) has a remarkably high boiling point because its molecules are held together by what exceptionally strong type of dipole-dipole intermolecular force?
Hydrogen bonding
Carbon dioxide (CO2) has a total of 16 valence electrons. When you draw its correct Lewis structure, how many total lone pairs are left sitting on the central Carbon atom?
0
Boron trifluoride (BF3) contains three highly polar B-F bonds, but the molecule has a symmetrical trigonal planar shape. What is the net dipole moment of this entire molecule?
0
What is the maximum number of electrons that can occupy an entire third principal energy level (n=3)?
18
Table salt (NaCl) requires a very high temperature (801°C) to melt because it is held together by a rigid crystal lattice of what specific type of chemical bond?
Ionic bond
If a central atom is bonded to three surrounding atoms and contains exactly one lone pair (like ammonia, NH3), what is its molecular geometry?
Trigonal pyramidal
Elements in Period 3 or higher can sometimes violate the octet rule by holding more than 8 valence electrons in their Lewis structure (like SF6). What is the technical term for this type of expanded outer shell?
Expanded octet
What is the molecular geometry of a molecule that has five bonding pairs and zero lone pairs around the central atom?
Trigonal bipyramidal