Chem Test 4
The H value for the reaction 1/2O2+Hg=HgO is -90.8 kg kj. How much heat is released when 97.5 g Hg is reacted with oxygen?
44.1 kJ
Calculate the room mean square velocity for the O2 molecules in a sample of O2 gas at 14.5 C.
473.4 m/s
Calculate the ratio of the effusion rates of N2 to N2O.
1.25
What is the specific heat capacity of a metal if it requires 177.5 J to change the temperature of 15.0 g of the metal from 25.00 C to 34.00 C?
1.31 J/g C
Gaseous chlorine is held in two separate containers at identical temperature and pressure. The volume of container 1 is 1.30 L, and it contained 6.70 mol of gas. The volume of container 2 is 2.26 L. How many moles of gas are in container 2?
11.6 mol
When 0.299 mol of a weak base is reacted with excess HCL, 6.91 Kj of energy is released heat. What is H for this reaction per mole of A- Consumed?
-23.1
Calculate the work for the expansion of CO2 from 1.0 to 5.2 liters against a pressure of 1.0 atm at constant pressure.
-4.2 L atm
The partial pressures of CH4, N2, and O2 in a sample of gas were found to be 163 mmHg, 475 mmHg, 551 mmHg, respectively. Calculate the mole fraction of oxygen.
0.463
A glass column is filled with mercury inverted in pool of mercury. The mercury column stabilizes at a height of 758 mm above the pool of mercury. What is the pressure of the atmosphere?
0.997 atm
How much heat is required to raise the temperature of a 6.69 g sample of iron from 25.0 C to 79.8 F?
165 J
For an ideal gas, which pairs of variables are inversely proportional to each other?
2 only; V and P
The heat combustion of benzene, C6H6, is -41.74 KJ/g. Combustion of 3.21 of benzene causes a temperature rise of 3.95 C in a certain bomb calorimeter. What is the heat capacity of this bomb calorimeter?
33.9 Kj/C
Order the following in increasing rate of effusion: F2, Cl2, NO, NO2, CH4
CL2<NO2<F2<NO<CH4
Hydrogen bonds account for which of the following observation?
For its molar mass, water has a high boiling point.
Which of of the following has a low density?
Gas
What is the strongest type of intermolecular force presents in NH2CH3?
Hydrogen bonding
Identify the characters of a liquid.
Indefinite shape, but definite volume.
Order the intermolecular forces from weakest to strongest.
London dispersion, dipole-dipole, hydrogen-bonding, and ionic.
The van der waals equation, -, incorporates corrections to the ideal gas law in order to account for the properties of real gases one of the corrections accounts for:
The finite volume of molecules
Which one of the following decreases as the strength of the attractive intermolecular forces increases?
The vapor pressure of a liquid.
Liquids with large intermolecular forces tend to have high surface tension.
True
Table salt and table sugar are both crystalline solids.
True
What is responsible for capillary action, a property of liquids?
Two of these.
According to the postulates of the Kinetic theory of gases, the average speed of the molecules of a given gas is proportional to the:
square root of the absolute temperature.
Using the information below, calculate Hf for PbO
-151.6 Kj/mol
At 25 C, the following heats of reaction are known: At the same temperature, calculate H for the reaction ClF+F2=Clf3
-108.7 KJ/mol
Given the pressure below, what is the boiling point for chloroform at standard pressure?
60 C
What is the kinetic energy of a 2.77 kg object moving at 85.5 km/hr?
7.81X10^2 Kj
Assign the appropriate labels to the phase diagram shown below.
A= gas, B= solid, C= liquid, D= triple point
Given the equation S+O2=SO2, H=-296 KJ, which of the following statements is are true?
All are true.
When calculating the Hrxn why is the HF for N2 not important?
Because nitrogen is in its standard elemental state and no energy is needed for this product to exist.
For a particular process q=20 kJ and w=15 kJ. Which of the following statements is true?
E=35 KJ
Methane exhibits stronger hydrogen bond interactions than that of ammonia.
False
Which of the following would have the lowest boiling point?
N2
Complete the following: Because real gas particles have attraction for one another:
Real gases act more ideally at higher temperatures and lower pressures