Ch.5-6 Review Worksheet

Ch.5-6 Review Worksheet

Ch.5-6 Review Worksheet

1. Given the following data:

K(s) → K(g) + 90. kJ

K(g) → K+(g) + e-+ 419 kJ

F2(g) → 2F(g) + 151 kJ

F-(g) → F(g) + e-+ 333 kJ

KF(s) → K+(g) + F-(g) + 803 kJ

Calculate ΔH for the reaction K(s) +1/2F2(g) → KF(s)

2. What is the amount of heat necessary to raise the temperature of 8.5 kg of water from 12.5 °C to
84 °C?

A)3.0 x 103 kJ

B)36 J

C)2.5 x 103 kJ

D)2.5 x 106 kJ

E)25 kJ

3. The specific heat of liquid water is 4.18 J/°C·g and the specific heat of carbon is 0.71 J/°C·g. A 10 gram sample of water and a 10 gram sample of carbon are each subjected to 155 J of heat. If both samples started at 25°C, which substance will have the higher final temperature, and by what magnitude?

A)Neither. They will have the same final temperature because the started at the same temperature and were exposed to the same quantity of heat.

B)water, by 28.7°C

C)carbon, by 18.1°C

D)water, by 3.47°C

E)carbon, by 215°C

4. A certain gas is compressed in a cylinder by a constant pressure of 9.0 atm from a volume of 35.0 L to 4.00 L. Calculate the work (w) for this process.

5. If 1700 cal of heat is added to a system while the system does work equivalent to 3000 cal by expanding against the surrounding atmosphere, the value of ΔE for the process is:

6. A 24.8 g piece of copper metal is heated from 22.5 °C to 178.6 °C. Calculate the heat absorbed by the metal. The specific heat of Cu is 0.385 J/g·°C.

7. A quantity of 1.535 g of liquid methanol (CH3OH) was burned in a constant-volume bomb calorimeter. Consequently the temperature of the water rose from 20.27 °C to 26.87 °C. If the mass of water surrounding the calorimeter was exactly 1000 g and the heat capacity of the bomb calorimeter was 1.75 kJ/°C, calculate the molar heat of combustion of liquid methanol .

8. Data:
(1) H2(g) + ½O2(g) → H2O(g) ΔH = -241.8 kJ
(2) H2(g) + ½O2(g) → H2O(l) ΔH = -285.8 kJ
On the basis of the above data, which of the following statements is false?

A)Reaction (1) is exothermic.

B)Reaction (2) is the formation reaction for H2O(l).

C)The reverse of reaction (2) is endothermic.

D)The energy content of H2O(g) is lower than H2O(l).

E)ΔH for the reaction: H2O(l) → H2O(g) is + 44 kJ/mol.

9. Given: C(s) + O2(g) → CO2(g) ΔH°rxn = -393 kJ
How many grams of C(s) must burn in this way to release 275 kJ of heat?

10. When 50. mL (50. g) of 1.00M HCl at 22.00 °C is added to 50. mL (50. g) of 1.00M NaOH at
22.00 °C in a coffee cup calorimeter, the temperature increases to 28.87 °C. What is the heat (q) of the reaction between HCl and NaOH? (The specific heat of the solution produced is 4.18 J/g·°C.)

11. A photon has a frequency is 3.90 x 1014 Hz? What is the energy of the photon?

12. Which of the following forms of electromagnetic radiation has the shortest wavelength?

A) microwaves

B) visible light

C) ultraviolet

D) radio waves

E) infrared

13. Calculate the wavelength of visible light having a frequency of 4.37 x 1014 s-1.

14. Which of the following combinations of quantum numbers is not allowed?

A) n = 3, l = 1, m(l) = 1, m(s) = ½

B) n = 1, l = 0, m(l) = 1, m(s) = ½

C) n = 4, l = 2, m(l) = 0, m(s) = ½

D) n = 2, l = 1, m(l) = -1, m(s) = -½

E) n = 5, l = 3, m(l) = -2, m(s) = -½

15. For a principle quantum number,n, equal to 5 ,what is the total
number of orbitals permitted?

16. The wavelength of a beam of light is 24 mm. What is the energy of one of its photons?

17. Calculate the frequency of the light emitted by a hydrogen atom during a transition of its electron from the n = 3 to n = 1 energy level, based on the Bohr theory.
Use the equation En= -2.18 x 10-18 J(1/n2)

18. How many photons of light having a wavelength of 656 nm are necessary to provide 1.0 J of energy?

19. For an excited hydrogen atom with the quantum number n equal to 9, which of the following statements is true?

A) The energy of the atom is less than the energy for the state in which n is equal to 8.

B) If l = 0, there are nine possible values for the magnetic quantum number ml.

C) The smallest value of the magnetic quantum number ml is -9.

D) The electron must be in one of the p orbitals.

E) The angular momentum quantum number l can have any of the values 0, 1, 2, 3, 4, 5, 6, 7, 8.

20. The Rydberg equation, with n1 = 1, predicts an ultraviolet series of spectral lines of atomic hydrogen. Which of the following wavelengths is not predicted by the equation?
Rydberg equation: 1/λ = (1.097 x 107 m-1) x (1/n12 - 1/n22)

A) 182 nm

B) 103 nm

C) 97 nm

D) 95 nm

E) 91 nm

Ch. 5-6 Review Worksheet KEY

1. 552 kJ

2. C

3. C

4. -279 j

5. -1300 cal

6. 1.49 x 103 J

7. -817 kJ/mol

8. D

9. 8.40g

10. -2.9 x 103 J

11. 2.60 x 10-19J

12. C

13. 686 nm

14. B

15. 25 or 16

16. 8.3 x 10-24 J

17. 2.92 x 1015 s-1

18. 3.3 x 1018

19. E

20. A