Atoms
Geometry
IMF
Polarization
Phase Change
100
Define Atomic Radius
Half the distance between the nuclei of two bonded atoms
100
Name the shape of BF3
Trigonal Planar
100
order the IMFs from weakest to strongest Hydrogen Bonds, London Dispersion, Dipole-Dipole
Dispersion < Dipole-Dipole < Hydrogen Bonds
100
What is the molecular polarity of H2 and why?
It is nonpolar, because its charges are distributed symmetrically and its geometric shape is symmetrical.
100
Liquid to Gas
Evaporation
200
Which atom is larger, Sodium or Magnesium
Sodium
200
What is the electron geometry and shape of NH3
electron geometry: tetrahedral shape: trigonal pyramidal
200
Identify the strongest intermolecular force present in pure samples of the following substances: SO2, H2O, CH2Cl2 SCO, PCl3, SO3
SO2: dipole-dipole forces H2O: hydrogen bonds CH2Cl2: dipole-dipole forces SCO: dipole-dipole forces PCl3: dipole-dipole forces SOC3: London Dispersion Forces
200
True or false. The Polarity of a bond increased as electronegativity increases
True
200
Gas to Solid
Deposition
300
What is the EN of C and F
Carbon: 2.5 Florine: 4.0
300
What is the electron geometry of POCl3
Tetrahedral
300
Rank the following from lowest boiling point to highest boiling point Br2, Cl2, I2
lowest bp: Cl2 < Br2 < I2 highest bp All are nonpolar molecules so only London dispersion forces are present. London dispersion forces get stronger as molar mass increases.
300
Order the following bonds according to polarity. H-H, O-H, Cl-H, S-H, F-H
H-H < S-H < Cl-H < O-H < F-H EN: S (2.5), Cl (3.0), O (3.5), F (4.0)
300
Which has the LOWEST vapor pressure? CH3COOH vs C2H6 CHF3 vs CF4 C20H42 vs C30H62 Br2 vs I2
CH3COOH CHF2 C30H62 I2
400
Boron (B) has an electronegativity of 2.0; chlorine (Cl) has an electronegativity of 3.0. Which of the following BEST describes a B-Cl bond? a)Ionic b)Polar Covalent c)Nonpolar
b) polar covalent (EN Dif is 1.0) Nonpolar: EN Dif <0.5 Polar Covalent: 0.5 - 2.0 Ionic: >2
400
What is the shape of XeCl2
Linear
400
Identify the substance that is likely to have the higher vapor pressure. CO2 or SO2
CO2 will have the higher vapor pressure. Vapor pressure tends to decrease as the strength of the intermolecular forces increase. Carbon dioxide is non-polar (dispersion forces only). Sulfur dioxide is polar (dipole-dipole forces are present).
400
Does the molecule have a dipole moment? If so, determine the direction of the bond polarity. H2S
Yes, a dipole moment is present. Direction of polarity is toward S.
500
Which of the following compounds would have the largest lattice energy? a) MgO b) NaBr c) CaO d) NaCl
MgO +2 and -2 charge and Mg is smaller that Ca
500
What is the shape of PCl5
trigonal bipyramidal
500
Circle true or false for the following statements. A. Water’s intermolecular forces are weaker than hexanes. B. Hexane has a higher vapor pressure than water. C. Hexane has a lower boiling point than water. D. Water has a higher surface tension than hexane. E. Water has lower viscosity than hexane. F. Water has higher molar heat of vaporization than hexane.
A False, B True, C True, D true, E false, F true
500
Predict which bond will be the most polar Ti-Cl, Si-Cl, Ge-Cl
Ti-Cl Ti has the least electronegativity
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