CH221 Practice Final-B

CH221 - 11:00 FINAL EXAM-B Practice

***DATA,* *CONSTANTS AND FORMULAS***

CONSTANTS
Avogadro    N= 6.022´ 10²³/mole
speed of light   c = 2.998 ´ 10⁸ m s^-1
mass electron m_e = 9.109 ´ 10^-31 kgPlanck   h = 6.626 ´ 10^-34 J-s
Bohr   a_o = 52.92 pm
Bohr   e_o = 2.179 ´ 10^-18 J
Rydberg   R_H = 1.097 ´ 10⁷ m^-1
FORMULAS
light wave:   ln = c
photon energy: E = hn

HYDROGEN-LIKE ATOMS
1/l = R_HZ²(1/n₁²-1/n₂²)
r_n = a_o n²/Z
E_n = - e_o Z²/n²CONVERSION FACTORS
1 J = 1 kgm² s^-²
1 cal = 4.184 J
angstrom 1 Å = 10^-10 m
1 nm = 10^-9 m
1 pm = 10^-12 m

SOLUBLE IONIC COMPOUNDS

STANDARD HEATS OF FORMATION

C₂H₅OH(g)	-235 kJ
C₂H₅OH(l)	-278 kJ
CH₃CHO(g)	-166 kJ
CH₃CHO(l)	-192 kJ
CO(g)	-110 kJ
CO₂(g)	-394 kJ
CO₂(aq)	-413 kJ
H₂O(g)	-242 kJ
H₂O(l)	-286 kJ
NH₃(g)	-46 kJ
NH₃(aq)	-81 kJ
NO₂(g)	33 kJ

PERIODIC TABLE OF ELEMENTS

Select one answer for each question:

1. A piece of iron is heated from 25°C to 115°C. What is the temperature change of the iron in degrees Fahrenheit?


	A)	-50°F
	B)	194°F
	C)	-130°F
	D)	162°F
	E)	50°F

2. How many picometers are there in one angstrom (Å)?


	A)	1000
	B)	100
	C)	10
	D)	1
	E)	0.1

3. What is the concentration of KNO₃ after 40.0 mL of water is added to 160.0 mL of 0.128 M KNO₃?


	A)	0.116 M
	B)	0.128 M
	C)	0.102 M
	D)	0.092 M
	E)	0.142 M

4. What volume of 0.125M barium hydroxide will exactly neutralize 200 mL of 0.160 M nitric acid?

A) 128 mL

B) 64 mL

C) 256 mL

D) 96 mL

E) 192 mL

5. The systematic name of the neutral compound ClO₄ is:


	A)	chlorine(VIII) oxide
	B)	perchlorate
	C)	tetraoxygen chloride
	D)	chloric oxide
	E)	chlorine tetraoxide

6. Give the sum of the coefficients when the combustion equation is balanced with lowest integers:

__C₆H₁₄ + __ O₂ __ CO₂ + __ H₂O


	A)	41
	B)	57
	C)	33
	D)	47
	E)	39

7. The total number of ions released when 1.62 moles of calcium chloride dissolve completely in water is:


	A)	1.95 ´ 10²⁴
	B)	4.88 ´ 10²⁴
	C)	2.93 ´ 10²⁴
	D)	3.21 ´ 10²⁴
	E)	1.46 ´ 10²⁴

8. Two successive chemical reactions A B and B C have yields of 25% and 64%, respectively. The yield for the overall conversion of A C is:


	A)	39%
	B)	16%
	C)	89%
	D)	25%
	E)	21%

9. Oxidation-reduction reactions involve transfer of


	A)	electrons from the reducing agent to the oxidizing agent
	B)	protons from the oxidizing agent to the reducing agent
	C)	electrons from the oxidizing agent to the reducing agent
	D)	protons from the reducing agent to the oxidizing agent

10. What is the volume of 1.25 moles of aluminum carbide (density = 2.36 g/mL)?


	A)	47.8 mL
	B)	76.3 mL
	C)	20.7 mL
	D)	55.6 mL
	E)	69.9 mL

11. Give the moles of electrons exchanged in the balanced equation

As₄S₆+ 9O₂ As₄O₆ + 6SO₂

		This type of redox problem will not be on the CH221 final
	A)	12
	B)	0
	C)	48
	D)	36
	E)	24

12. Find the oxidation number of nitrogen in a compound N_xO_y if 7.143 g of the compound contains 2.597 g of oxygen.


	A)	1
	B)	4
	C)	3
	D)	2
	E)	5

13. Use the following reaction data

Fe₂O₃ + 3CO 2Fe + 3CO₂ , DH = -26.8 kJ

FeO + CO Fe + CO₂, DH = -16.5 kJ

to find the enthalpy change for the reaction

Fe₂O₃ + CO 2FeO + CO₂


	A)	27.7 kJ
	B)	10.3 kJ
	C)	6.2 kJ
	D)	-43.3 kJ
	E)	-10.3 kJ

14. Which of these samples of ionic compounds releases the largest number of ions when placed in water?


	A)	0.3 mole of Al(OH)₃
	B)	0.2 mole of NaCl
	C)	0.2 mole of PbBr₂
	D)	0.1 mole of (NH₄)₂CO₃
	E)	0.4 mole of CaSO₄

15. How many moles of electrons can be transferred in a fuel cell based on the equation

2H₂+ O₂ 2H₂O

with 12 g of hydrogen and 72 g of oxygen. (HINT: this involves a limiting reactant.)

		this type of redox problem will not be on the CH221 final
	A)	18
	B)	6
	C)	15
	D)	9
	E)	12

16. Identify the oxidizing agent in the equation:

H₃IO₆²^- + HSnO₂^- + H₂O IO₃^- + Sn(OH)₆²^-


A)		HSnO₂^-
B)		Sn(OH)₆²^-
C)		H₂O
D)		IO₃^-
E)		H₃IO₆²^-

17. Which mixture of solutions does not produce a solid precipitate?


	A)	potassium iodide and lead(II) nitrate
	B)	silver(I) nitrate and sodium chloride
	C)	calcium nitrate and sodium sulfide
	D)	copper(II) sulfate and ammonium carbonate
	E)	sodium hydroxide and cobalt(II) chloride

18. What is the wavelength of the electromagnetic radiation from a cell phone that operates at 8.50 ´ 10⁸ s^-1 ?


	A)	35.3 cm
	B)	25.4 cm
	C)	15.6 cm
	D)	52.9 cm
	E)	43.1 cm

19. What is the principal quantum number of the occupied orbital in the ground state of the hydrogen atom?


	A)	2
	B)	1
	C)	0
	D)	-1
	E)	-2

20. What is the angular momentum quantum number for a 3p orbital?


	A)	1
	B)	3
	C)	2
	D)	0
	E)	4

21. According to ________ a particle of mass m and velocity v has a wavelength l = h/mv.


	A)	Planck
	B)	Rydberg
	C)	Bohr
	D)	Einstein
	E)	de Broglie

22. The allowed values of m_l when n = 3 and l = 2 in the hydrogen atom are:


	A)	0, 1, 2, 3
	B)	3, 2, 1, 0, -1, -2, -3
	C)	0, 1, 2
	D)	2, 1, 0, -1, -2
	E)	1, 0, -1

23. Which of these shapes are consistent with atomic orbitals that have n = 2?


1)	2)	3)	4)	5)



	A)	3, 5
	B)	1, 2, 4
	C)	1, 3, 5
	D)	2, 3, 4, 5
	E)	1, 5

24. What is the radius of a hydrogen-like ion F⁸⁺ with n = 2 in the Bohr model?


	A)	30.2 pm
	B)	23.5 pm
	C)	34.6 pm
	D)	18.7 pm
	E)	26.5 pm

25. Which of these transitions in the hydrogen atom emits radiation at the longest wavelength?


	A)	4 3
	B)	2 1
	C)	5 4
	D)	3 2
	E)	100 1

26. Which atom has the electron configuration 1s²2s²2p⁶3s²3p²?


	A)	oxygen
	B)	aluminum
	C)	sulfur
	D)	phosphorus
	E)	silicon

27. The maximum number of 4d electrons is:


	A)	12
	B)	18
	C)	14
	D)	10
	E)	16

28. What is the highest value of n in the electron configuration for Pb?


	A)	6
	B)	3
	C)	7
	D)	5
	E)	4

29. How many “p” electrons are there in Br?


	A)	18
	B)	16
	C)	17
	D)	21
	E)	15

30. In which atom does the electron configuration in the highest unfilled subshell look like this?


	A)	Si
	B)	S
	C)	Sc
	D)	Sn
	E)	Sb

31. What is the energy of one mole of photons whose wavelength is 319 nm?


	A)	288 kJ
	B)	375 kJ
	C)	623 kJ
	D)	324 kJ
	E)	415 kJ

32. What mass of oxygen is consumed in the combustion of 63.4 g of acetaldehyde by the equation

2CH₃CHO(l) + 5O₂(g) 4CO₂(g) + 4H₂O(l)


	A)	110 g
	B)	57.6 g
	C)	233 g
	D)	115 g
	E)	221 g

33. How much heat is produced in the preceding Question 32?


	A)	1609 kJ
	B)	1736 kJ
	C)	1681 kJ
	D)	1592 kJ
	E)	1719kJ

CH221 - 11:00 FINAL EXAM-B Practice

DATA, CONSTANTS AND FORMULAS

SOLUBLE IONIC COMPOUNDS

***DATA,* *CONSTANTS AND FORMULAS***