Download Chemistry Exam 1 Form 2: Multiple Choice Questions and more Study Guides, Projects, Research Chemistry in PDF only on Docsity!
1) The answer (using the correct number of significant figures) to the following is ________.
(𝟏𝟏𝟏𝟏. 𝟕𝟕𝟕𝟕𝟕𝟕 + 𝟏𝟏. 𝟏𝟏𝟏𝟏) ∗ 𝟑𝟑. 𝟗𝟗𝟗𝟗𝟗𝟗 ∗ 𝟏𝟏. 𝟑𝟑𝟕𝟕 ÷ 𝟐𝟐. 𝟕𝟕𝟕𝟕𝟕𝟕 + 𝟏𝟏. 𝟕𝟕𝟑𝟑𝟕𝟕𝟕𝟕
A. 12. B. 48. C. 48. D. 32. E. none of the above
2) Sb has two naturally occurring isotopes: 121 Sb has a mass of 120.90 amu, and 123 Sb has a mass of 122.90 amu. Use the atomic weight of Sb from the periodic table to determine the abundance of the 121 Sb isotope.
A. 57.0 % B. 85.0 % C. 43.0 % D. 14.0 % E. none of the above
3) Express the density of mercury (11. 𝒈𝒈 𝒎𝒎𝒎𝒎 ) in^
𝒍𝒍𝒍𝒍 𝒇𝒇𝒇𝒇 𝟑𝟑.
A. 849 lb/ft 3 B. 724 lb/ft 3 C. 5.90 lb/ft 3 D. 131 lb/ft 3 E. none of the above
4) How many significant figures are in 18030000 microliters?
A. 8 B. 3 C. 5 D. 4 E. None of these
( 15. 89 ) ∗ 3. 999 ∗ 1. 36 ÷ 2. 775 + 1. 6366 =
% Abundance = % 121 Sb + % 123 Sb = 100% Or (^121) Sb + 123 Sb = 1 (^123) Sb = 1 – 121 Sb
AW (Sb) = 121 Sb + 123 Sb 121.76 = (120.90 * x) + (122.90 * (1-x)) = 120.90 x + 122.90 - 122.90 x = − 2 .00 x + 122. 121.76 – 122.90 = − 2.00 x − 1.14 = − 2.00 amu x x = −1. 14 −2. 00 = .570^ 𝑜𝑜𝑜𝑜^ 57.0%^
(^121) Sb
𝑔𝑔 𝑚𝑚𝑚𝑚
∗
1 𝑙𝑙𝑙𝑙 453.6 𝑔𝑔
∗
1 𝑚𝑚𝑚𝑚 1 𝑐𝑐𝑚𝑚^3
∗ �
- 54 𝑐𝑐𝑚𝑚 1 𝑖𝑖𝑖𝑖
�
3 �
12 𝑖𝑖𝑖𝑖 1 𝑓𝑓𝑓𝑓
�
3
= 11.
𝑔𝑔 𝑚𝑚𝑚𝑚 ∗
1 𝑙𝑙𝑙𝑙 453.6 𝑔𝑔 ∗
1 𝑚𝑚𝑚𝑚 1 𝑐𝑐𝑚𝑚^3 ∗ �
16.4 𝑐𝑐𝑚𝑚^3 1 𝑖𝑖𝑖𝑖 3 � ∗ �
1728 𝑖𝑖𝑖𝑖 3 1 𝑓𝑓𝑓𝑓 3 �
= 724
𝑙𝑙𝑙𝑙 𝑓𝑓𝑓𝑓 3
5) How many significant figures are in 0.12980000?
A. 6 B. 3 C. 8 D. 4 E. None of these
6) What is the mass of a rectangular piece of copper with dimensions of 144 mm x 144 mm x 8.9 cm? The density of copper is 6.92 g/mL.
A. 4.05 x 10 3 g B. 1.96 x 10 4 g C. 2.47 x 10 2 g D. 1.65 x 10 4 g E. none of the above
7) The lethal dose of potassium cyanide (KCN) taken orally is 1.60 mg/kg of body weight. Calculate the lethal dose of potassium cyanide taken orally by a 140 lb person. (1 lb = 453.6 g)
A. 36 mg KCN B. 9.2 x 10 4 mg KCN C. 92 mg KCN D. 102 mg KCN E. none of the above
8) How many significant figures are in 3.0000 g?
A. 1 B. 3 C. 4 D. 5 E. None of these
9) The charge on the zinc in the salt ZnF2 is ________.
A. 3+ B. 2+ C. 1+ D. 1- E. 2-
10) Diazodinitrophenol (DDNP) is an explosive with a density of 1.63 g/mL. What volume (cm 3 ) would a 1.20 pound sample of DDNP occupy? (1 lb = 453.6 g)
A. 1.35 x 10 -3^ cm 3 B. 278 cm 3 C. 3.59 x 10 -3^ cm 3 D. 334 cm 3 E. none of the above
First solve for volume (in cm^3 conver�ng mm to cm): V = lwh = 14.4 cm * 14.4 cm * 8.90 cm = 1.85 x 10 3 cm^3
Using Density Equa�on d=m/V; m=dV 𝑚𝑚 = 1.85 𝑥𝑥 103 𝑐𝑐𝑚𝑚^3 ∗
6.92 𝑔𝑔 1 𝑐𝑐𝑚𝑚^3
= 1. 28 𝑥𝑥 104 𝑔𝑔
453 .6𝑔𝑔 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏 𝑤𝑤𝑤𝑤 1 𝑙𝑙𝑏𝑏 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏 𝑤𝑤𝑤𝑤 ∗^
1 𝑘𝑘𝑔𝑔 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏 𝑤𝑤𝑤𝑤 1000 𝑔𝑔 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏 𝑤𝑤𝑤𝑤 ∗^
- 60 𝑚𝑚𝑔𝑔 𝐾𝐾𝐾𝐾𝐾𝐾 1 𝑘𝑘𝑔𝑔 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏 𝑤𝑤𝑤𝑤 = 102^ 𝑚𝑚𝑔𝑔^ 𝐾𝐾𝐾𝐾𝐾𝐾
Using Dimension Analysis
1.20 𝑙𝑙𝑙𝑙 ∗
453.6 𝑔𝑔 1 𝑙𝑙𝑙𝑙
∗
1 𝑚𝑚𝑚𝑚 1.63 𝑔𝑔
∗
1 𝑐𝑐𝑚𝑚^3 1 𝑚𝑚𝑚𝑚
= 334 𝑐𝑐𝑚𝑚^3 Using Density Equa�on d=m/V; V=m/d
V = 𝑚𝑚 𝑏𝑏 =^
- 20 𝑙𝑙𝑏𝑏∗^4531 𝑙𝑙𝑙𝑙.^6 𝑔𝑔
- 63 𝑔𝑔 1 𝑚𝑚𝑚𝑚
=
- 𝑔𝑔
- 63 𝑔𝑔 1 𝑚𝑚𝑚𝑚
= 334 𝑚𝑚𝑚𝑚 = 334 𝑐𝑐𝑚𝑚 3
𝑍𝑍𝑖𝑖^2 +^ 𝐹𝐹 2 −^1
15)
𝟐𝟐.𝟑𝟑𝟑𝟑 ∗ 𝟏𝟏𝟏𝟏𝟏𝟏 𝟕𝟕.𝟐𝟐𝟏𝟏𝟕𝟕 ∗ 𝟏𝟏𝟏𝟏𝟕𝟕 (𝟏𝟏𝟏𝟏𝟏𝟏.𝟏𝟏𝟕𝟕−𝟏𝟏𝟕𝟕.𝟖𝟖)∗ 𝟏𝟏𝟏𝟏𝟐𝟐^
A. 1.8 x 10 - B. 3.8 x 10 - C. 1.8 x 10 - D. 3.8 x 10 - E. none of the above
16) What is the formula weight of 𝑹𝑹𝑹𝑹𝟑𝟑(𝑷𝑷𝑷𝑷𝟏𝟏)𝟐𝟐?
A. 498. B. 496. C. 495. D. 527. E. none of the above
17) Oleic acid is a common fatty acid that occurs naturally in animal and vegetable fats. It is also olive oil. A shorthand way to write its chemical structure is CH 3 (CH 2 ) 7 CHCH(CH 2 ) 7 COOH. What is oleic acid's empirical formula?
A. C 3 H 5 O B. C 3 H 17 O C. C 8 H 15 O D. C 9 H 17 O E. C 18 H 34 O 2
18) How many protons, neutrons, and electrons are in an ion of 192 Os 3+
A. 76 p+, 116 n°, 76 e- B. 73 p+, 116 n°, 76 e- C. 76 p+, 116 n°, 73 e- D. 73 p+, 76 n°, 116 e- E. 76 p+, 76 n°, 116 e-
19) Of the following, identify all of the molecular compounds:
PI 5 , NaBr, SBr 2 , Mg(NO 2 ) 2 , FeI 3, ZnSO 4 , N 2 O 5
a) PI 5 and N 2 O (^5) b) PI 5 , SBr 2 , and N 2 O (^5) c) PI 5 , FeI 3 , and N 2 O (^5) d) NaBr, Mg(NO 2 ) 2 , and ZnSO 4 e) PI 5 , SBr 2 , FeI 3, ZnSO 4 , and N 2 O 5
(11.13 − 2.6) ∗ 2.33^ ∗^10
4 6.215 ∗ 106 ( 101. 06 − 16. 8 ) ∗ 102 =
(8.5) ∗ 3.75 𝑥𝑥 10 − ( 84. 3 ) ∗ 102 = 3.8 𝑥𝑥 10 −
3 * Rh + 2P + 8 O
3102.91 amu + 2 30.97 amu + 8*16.00 amu = 308.73 amu + 61.94 amu+ 128.00 amu = 498.67 amu
CH 3
(CH 2 ) 7
CH
CH
(CH 2 ) 7
COOH
CH 3
C 7 H 14
CH
CH
C 7 H 14
CHO 2
C 18 H 34 O 2
C 16 H 30 O 2
Os (Atomic Number) = 76 Mass number = protons + neutrons Neutrons = 192 – 76 = 116 P = 76 E = 76 – 3 = 73
20) How many protons, neutrons, and electrons are in an atom of 65 Cu?
A. 29 p+, 29 n°, 65 e- B. 29 p+, 36 n°, 29 e- C. 36 p+, 29 n°, 34 e- D. 34 p+, 36 n°, 29 e- E. 65 p+, 29 n°, 65 e-
21) What is the name of this compound, 𝑹𝑹𝑹𝑹𝟑𝟑(𝑷𝑷𝑷𝑷𝟏𝟏)𝟐𝟐
A. Rhodium (III) phosphate B. Rhodium (II) diphosphate C. Rhodium (II) phosphate D. Trirhodium diphosphate E. none of the above
22) What is the name of this compound 𝑪𝑪𝑪𝑪(𝑵𝑵𝑷𝑷𝟐𝟐)𝟐𝟐?
A. copper I nitrate B. copper II nitrate C. copper I nitrite D. copper II nitrite E. monocopper dinitrate
23) What is the name of the compound whose formula is Crl3?
A. chromium iodide B. chromium (III) iodide C. chromic tri-iodide D. chromium (III) tri-iodide E. monochromium tri-iodide
24) Many familiar substances have common, unsystematic names. For the following substance, give the correct systematic name. Milk of magnesia, 𝑴𝑴𝒈𝒈(𝑷𝑷𝑶𝑶)𝟐𝟐
A. magnesisum dihydroxide B. magnesium hydroxide C. magnesium (II) hydroxide D. magnesium dioxide dihydride E. monomagnesium dihydroxide
25) How many hydrogen atoms are in the following compound: (𝑵𝑵𝑶𝑶𝟏𝟏)𝟑𝟑 𝑷𝑷𝑷𝑷𝟏𝟏?
A. 3 B. 4
C. 7
D. 12
E. None of these
Cu (Atomic Number) = 29 Mass number = protons + neutrons Neutrons = 65 – 29 = 36 P = 29 e = 29
𝑅𝑅ℎ 32 +^ (𝑃𝑃𝑆𝑆 4 ) 2 −^3
𝐾𝐾𝐶𝐶 12 +^ (𝐾𝐾𝑆𝑆 2 ) 2 −^1
𝐾𝐾𝑜𝑜 13 +^ 𝐼𝐼 3 −^1
