Gases
A sample of Nitrogen gas in a 5.6 L container at a temperature of 326 K exerts a pressure of 9.3 atm. What is the mass of the sample?
54.5 g
Calculate w, and determine whether work is being done by the system or on the system when 512 J of heat is released and delta U= 745 J
1257 J
What is the wavelength (nm) of light having a frequency of 7.9x 10^13 Hz?
3.49 x10^-15 nm
_____ , which stands for orbital angular momentum, is one of the four quantum numbers used to characterize an electron in an atom.
L
Hess’ Law be used to determine enthalpy of formation of a particular substance (True/False)
True
A mixture of gases contains .38 mole CH4, .74 mol C2H6, and .32 mole C3H8. The total pressure is 3.5 atm. Calculate partial pressure of C2H6
1.76 atm
Convert 676 kJ to calories
161568.0 cal
From the following data (C (gr) means graphite):
C (gr) +O2 (g)-> CO2 (g) delta H: -450.3 kJ/mol
H2 (g) +½ O2 (g)-> H2O (l) delta H: -295.6 kJ/mol
2C2H6 (g) + 7O2-> 4CO2 (g) + 6H2O (l) delta H: -4120.8 kJ/mol
C2H6 (g)->2C (gr)+3H2 (g)
-546 kJ/mol
What are the permissible values for the quantum numbers associated with 3s?
n=3, ℓ= 0, mℓ=0, ms= +/- ½
Calculate the volume (L) of 200g of CO2 at STP
100.8 L
If 3236 g of S reacts with oxygen calculate the volume of SO2 gas (L) formed at 423 K and 3.46 atm. S(s) + O2(g) → SO2 (g)
1014.5 L
A 5.66 kg piece of copper metal is heated from 25 degrees Celsius to 400 degrees Celsius. Calculate the heat absorbed (kJ) by the metal. The specific heat of copper metal is 0.385 J/g* C.
817.163 kJ
Calculate the enthalpy change using given data.
H2 (g) +O2 (g)-> H2O2 (l)
H2O2 (l) -> H2O (l) + ½ O2 (g) delta H: -98 kJ
2H2 (g) + O2 (g) -> 2H2O(l) delta H: -571.6 kJ
-375.6 kJ
How many electrons can four d orbitals have?
40
True or false: D orbitals can hold two electrons per orbital.
False
Calculate the root-mean-square speeds of CO2 at 35 C
417.84
A 45 g sample of a substance is initially at 30.5 degrees Celsius. After absorbing 1,567 J of heat, the temperature of the substance is 122.6 degrees Celsius. Calculate the specific heat of the substance (J/g*c).
0.378 J/g*c
What is the value of ni if the photon emitted has a wavelength of 94.9 nm and nf=1.
5
True or false: An electron in an atom is in n=4. One of the mℓ values has to be
-4,-3,-2,-1,0,1,2,3,4.
False
A gas known to have a formula of CHx was found to effuse at a rate that is 1.41 times the rate of effusion of oxygen gas. Determine the molar mass of CHx and the value of x.
16 g/mol, x = 4
An unknown gas effused in 10 minutes. In the same conditions, it takes an equal volume of N2 20 minutes to effuse. Calculate the molar mass of the unknown gas.
7 g/mol
A student mixes 88.6 g of water at 74.3 degrees Celsius with sample water at 24.8 degrees Celsius in an insulated flask. If the final temperature of the combined water is 58 degrees Celsius, what is the mass of the sample of water at 24.8 degrees Celsius?
43.5 g
Calculate the wavelength in (nm) of a photon emitted by a hydrogen atom when its electron drops from the n=7 to n=2 state.
397 nm
List all the possible values of quantum numbers for a certain atom who has a n=3 quantum level.
ℓ= 0,1,2
mℓ= (-2,2)
ms= +/- ½
List all the possible values of quantum numbers for a certain atom who has a n=5 quantum level.
ℓ= 0,1,2,3,4
mℓ= (-4->4)
ms= +/- ½