EXAM I REVIEW
1.)The gas law that states pressure is indirectly proportional to volume is named after which scientist?(a)Avogadro
(b)Boyle
(c)Charles
(d)Dalton
2.)Which of the following is not an example of a state function?
(a)Enthalpy
(b)Entropy
(c)Gibbs free energy
(d)Heat
3.)For which reaction does the standard heat of reaction equal the standard heat of formation of methane?
(a)CH4 (g) → C (s) + 4H(g)
(b)CH4 (g) → C (s) + 2H2(g)
(c)C (s) + 4H (g) → CH4(g)
(d)C (s) + 2H2(g) → CH4(g)
4.)A gas is compressed in a constant pressure process. If the internal energy of the gas remains constant throughout the process, what must be true regarding the heat transferred in this process?
(a)Heat must flow from the surroundings to the system
(b)Heat must flow from the system to the surroundings
(c)The heat for this process must equal zero
(d)The heat will first flow from the surroundings to the system and then flow from the system to the surroundings
5.)For a particular process that is carried out at constant pressure, q= 125 kJ and w=-15 kJ. Therefore,
(a)∆E=110 kJ and ∆H=125 KJ
(b)∆E=125 kJ and ∆H=110 kJ
(c)∆E= 125 kJ and ∆H=140 kJ
(d)∆E=140 kJ and ∆H=-140 kJ
6.)Which of the following relationships would yield a straight line if the data were plotted in a y vs. x format (Circle all that apply)?
(a)V vs. T
(b)P vs. T
(c)1/P vs. T
(d)1/V vs. n
7.)What gas laws did Scientist Boyle, Charles, and Avogadro discover? Draw the graphs of each has law.
8.)A 0.75 g sample of KClis added to 35.0 g of H2O in a calorimeter and stirred until it dissolves. The temperature of the solution drops from 24.8 to 23.6 oC. The specific heat capacity of the solution is 4.184 J/g*oC and there is no heat lost to the surroundings.
a.)Is this process exothermic?
b.)What is the heat of dissolution of KCl (in kJ/mol of KCl)?
9.)Use the following information to calculate the bond dissociation energy (D) for the C=) double bond.
2CH3OH(l) + 3O2(g) → 2CO2(g) + 4H2O(g)∆Horxn= -1453kJ
D (kJ/mol)C-H / 410
C-O / 350
C=C / 728
O-H / 460
O-O / 180
O=O / 498
10.)A gaseous compound has the empirical formula CH. A sample of this gas at 50.00C and pressure of 1.00 atm is found to have density of 0.984 g/L. What is molecular formula of the gas?
11.)Consider the following reaction performed at constant pressure and temperature:
A2 (g) + 2B(g) → 2AB(g)
a.)Is the enthalpy change greater than, less than, or equal to the change in the internal energy?
Circle One: ∆H> ∆E∆H< ∆E∆H= ∆E
b.)Explain why bond dissociation energies must be always be positive values.
12.)According to the United States National Weather Service, the air temperatures in California reached 78oF on January 1, 2016, when the atmospheric pressure was 1024 mbar. Celebrities attending the Oscars at the Dolby Theatre®at Hollywood & Highland Center are concerned about the density of the air.What was the density of the air in g/L? Assume the average molar mass of air is 28.8 g/mol.
13.)What is the equation for heat of formation (∆Hf)?
14.)Calculate the enthalpy of reaction for NO (g) + O (g)→NO2(g)given the following data:
2O3(g)→3O2 (g)∆H=-427 KJ
O2(g)→2O(g)∆H=495 kJ
NO (g) + O3(g)→NO2 (g) + O2(g)∆h=-199 kJ
15.)Calcium metal reacts with water to produce hydrogen gas:
Ca + 2H2O→Ca(OH)2 + H2
In a given experiment, 825 mL of the gas is collected over water at 25oC at a pressure of 0.967 atm. If the partial pressure of water at 25oC is 0.0313 atm, calculate the mass of H2 produced.
16.)In a calorimeter, 100.0 mL of 0.500 M HCl was mixed with 300.00 mL of 0.100 M Ba(OH)2. The initial temperature of each solution was 25.00oC. After the reaction completed, the final temperature of the solution was 26.76oC.
2HCl + Ba(OH)2→BaCl2 + 2H2O
a.)Is this an exothermic or endothermic process? Explain.
b.)Calculate the enthalpy of the reaction. Give your answer in KJ/mol reaction. Assume denistyy and heat capacity are 1.00 g/mL and 4.18 J/g*oC. You can assume that the heat absorbed by the calorimeter is negligible.