Stoichiometry
Calculate the mass (grams) of chlorine gas that can be produced by the electrolysis of 25.0 kg of sodium chloride in concentrated aqueous solution.
2NaCl(aq) + 2H2O(l) ----> 2NaOH (aq) + Cl2 (g) + H2 (g)
15,200 g Cl2
How many liters of a 0.239 M NaOH solution contain 0.310 mol of NaOH
1.30 L
Match each term to its definition:
1. Thermochemistry
2. Energy
3. Work
4. Kinetic Energy
5. Potential Energy
a. a force acting over a distance
b. energy of motion
c. the capacity to do work or transfer heat
d. the study of the relationships between chemistry and energy.
e. energy related to position; the energy stored in an object
1 to d
2 to c
3 to a
4 to b
5 to e
A 2.90 L sample of hydrogen gas has a pressure of 0.250 atm. What is its volume if its pressure is increased to 2.40 atm at constant temperature?
0.302 L
Calculate the mass of chlorine gas that will react with 1.95 g of phosphorus to form solid phosphorus pentachloride, PCl5
5Cl2 (g) + 2P (s) ---> 2PCl5
11.2 g
To what volume should you dilute 0.240 L of a 15.3 M NaOH solution to obtain a 3.12 M NaOH solution?
1.18 L solution
P4 + 5O2 --> P4O10; delta H = -3013 kJ
-5,691 kJ
A 713 mL sample of helium gas, initially at 0 degrees Celsius, is heated at constant pressure. If the final volume of the gas is 0.923 L, what is its final temperature in degrees Celsius?
81 degrees Celsius
(0 degrees Celsius has no decimals, so give temperature answer to the same number of decimal places)
Calculate the number of moles of reactants and products that are present after the reaction of 1.740 mol CH3OH with 0.600 mol O2 is complete.
2CH3OH (g) +3O2 (g) --> 2CO2 (g) + 4H2O (g)
O2: 0 mol (all used, limiting reagent)
CO2: 0.4 mol produced
H2O: 0.8 mol produced
CH3OH: 0.4 mol reacted, 1.34 mol remaining
What volume of a 0.341 M KCl solution is required to react exactly with 34.0 mL of a 0.215 M Pb(NO3)2 solution?
2KCl (aq) + Pb(NO3)2 (aq) --> PbCl2 (s) + 2KNO3 (aq)
4.29 mL or 0.0429 L
27.0 g sample of a metal at 89.3 Celsius is placed in 40.1 g of water at 10.48 Celsius. the final temperature of the system is 15.8 Celsius.
Calculate the specific heat of the metal. Which of the metals below is it most likely to be?
Al Cm: 0.892 J/gxC
Cr Cm: 0.45 J/gxC
Cu Cm: 0.385 J/gxC
Pb Cm: 0.13 J/gxC
Cm = 0.45 J/gxC
Matches with Chromium
Calculate the volume of 71.72 g carbon dioxide gas at 21.85 degrees Celsius and 1.14 atm.
34.6 L
What mass of Na2SO4 will be formed by addition of 7.93 g NaHCO3 in aqueous solution to an aqueous solution containing 3.21 g H2SO4?
4.65 g Na2SO4
Calculate the molar mass of an unknown alkali hydroxide if it took 37.25 mL of 1.017 M HCl to neutralize 25.00 mL of a solution of the base (metal hydroxide) that contained 2.125 g of the solid, pure metal hydroxide
MM = 56.1 g/mol
unknown alkali hydroxide = KOH
Use the delta H values for equations 1, 2, and 3 to calculate delta H for the following reaction.
C2H2 + 2H2 --> C2H6
1. 2C2H2 + 5O2 --> 4CO2 + 2H2O; H=-2320kJ
2. 2C2H6 + 7O2 --> 4CO2 + 6H2O; H = -3040kJ
3. 2H2 + O2 --> 2H2O; H = -572kJ
-212 kJ
Calculate the number of moles of oxygen gas in a 1.94 L container at 24 degrees Celsius and 749 torr
0.078 mol