Chemical Reactions, Empirical Formulas, and Limiting Reactants
Energy
Calorimetty
Solids, Liquids, and Gases
VESPR Geometries
100
Chlorine exists as two isotopes: 35 and 37 atomic weights. If the average atomic weight of chlorine is 35.45, what is the approximate abundance of 37Cl?
25%
100
Does the kinetic energy of a ball increase or decrease as it moves higher?
Decrease
100
What are the units of specific heat capacity?
J/gC
100
If there were two samples of the same metal, one with the body-center cubic structure and the other with the
face-centered cubic structure, which would be more dense?
Face-centered
100
What is the molecular geometry of water?
Bent
200
How many H atoms are there in 1.75g of (NH4)2CO3?
8.773 x 10^22 H atoms
200
A system releases 66.1 kJ of heat to its surroundings while the surroundings do 44.0 kJ of work on the system. What is delta E?
-22.1 kJ
200
You want to heat water to make coffee. How much heat (in kJ) must be used to raise the temperature of 0.180 kg water from 15.0 C to 96.0 C? The heat capacity of water is 4.184 J/gC.
q=CmdeltaT
61.0 kJ
200
What are all the possible intermolecular forces (IMF) that exist for NH3?
Hydrogen bonding, dipole-dipole, and london dispersion
200
What is the electron geometry of SF4?
Trigonal bipyramidal
300
A compound contains 41.86% Mg, 54.86% O, and 3.46% H by mass. What is its empirical formula?
MgO2H2
300
Calculate the energy of a photon whose frequency is 6.75 x 10^12 s-1.
4.47 x 10^-21 J
300
10.0 g metal (C=9.75 J/gC) at 120.0 C is dropped into 100 mL of water (C=4.184 J/gC) at 25.0 C. What is T final?
43.0 C
300
Argon gas, Ar, is contained in a steel cylinder with a volume of 9.76 L. The temperature is 21.0 ˚C, and the
mass of the Ar is 80.7 g. What is the pressure of the Ar?
5 atm
300
What is the hybridization of nitrogen in NH3?
sp3
400
10.00g of MO is heated and converted into M and O2 producing 1.044g of O2. What element is M?
Ba
400
Calculate the wavelength of the radiation released when an electron moves from n=6 to n=2 in the hydrogen atom.
4.84 x 10 ^-19 J
400
4.50 g of ethanol was burned in a constant volume bomb calorimeter (calorimeter constant = 1285 J/C) which contained 125 g water. After the reaction, the temperature of the water and calorimeter increased from 19.23 to 85.32 C. What is the deltaH of the reaction for ethanol? Start by writing the combustion reaction.
-1236 kJ
400
Arrange the following in order of increasing London forces: SiCl4, CCl4, GeCl4
Least: CCl4
SiCl4
Greatest: GeCl4
400
What is the molecular geometry of ClF3?
T-shape
500
What volume of 0.45M Na3PO4 is required to precipitate all the AgNO3 (aq) as insoluble Ag3PO4 (s) from 25mL of 0.22M AgNO3 (aq)?
4.07 mL
500
Use the de Broglie relationship to determine the wavelength of a lithium atom moving at 2.5 x 10^5 m/s.
2.3 x 10^-13 m
500
When 2.50 g H2SO4 (l) at 21.5 C was added to 75.0 g water at 21.5 C, the temperature of the solution increased to 29.0 C. What is the value of deltaH of the reaction for H2SO4 (l) to H2SO4 (aq)?
-95.4 kJ
500
A gas sample is heated from -20˚C to 57˚C and the volume is increased from 2.0L to 4.5L. If the initial
pressure is 0.125 atm, what is the final pressure?