Units
The units for energy
Joules (J) or kiloJoules (kJ)
If the volume of a gas doubles, its pressure will...
Halve
Calculate the moles of Mg in a 12.2-gram sample of Mg.
0.502 moles Mg
Congratulations! You guessed instead of leaving the answer blank and got it right!!! Free 100 points.
+100 points
The units for solution concentration
Molarity (moles / Liter)
A 5.0-gram sample of CaCO3 contains _____ moles (molar mass = 100 g/mol)
0.05 mol
A 0.200-mol sample of H2 at 20ºC has a pressure of 1.22 atm. Calculate its volume.
3.94 L H2
moles --> grams
Molar Mass
(n)(MM) = x
The units for the molar mass of a compound
grams per mole (g/mol)
A sample of HC2H3O2 has a pH of 5. The concentration of [H3O+] in this solution is...
1x10–5 M
A 100 mL sample of 2.25M CuCl2 is added to 450 mL of distilled water. Calculate the new concentration of the solution.
0.409 M CuCl2
h and c
(h)(c) / (E) = x
The units for the standard entropy change, ∆Sº
J / mol•K
If the ∆Sº is positive (+∆Sº) and the ∆Hº is negative (–∆Hº), the value of ∆Gº is going to be favored at...
All Temperatures
(–∆Gº will always happen)
An iron cube is placed in 250-grams of water at 23.0ºC. The temperature of the water increases to 29.0ºC. Calculate the heat, q, absorbed by the water.
(c for water = 4.2 J/gºC)
6,300 J
pH --> [OH–]
Kw and [H+]
(1) 10–pH = [H+]
(2) 1x10–14 / [H+] = [OH–]
The units for a first-order rate constant, k
time-1
(example: seconds–1)
Show the setup to calculate the solubility of the following salt:
AgCl(s) --> Ag+ (aq) + Cl– (aq) Ksp = 1.8x10–10
s = sqrt(1.8x10–10)
A copper battery runs using a current of 0.200 A to reduce Cu+2 --> Cu (s). Calculate how long it will take to plate 0.223 g of Cu.
3,390 seconds
mass of gas --> volume of gas
D
molar mass & 22.4 L•mol–1