Name ______
Chemistry I-H
Midterm Study Guide
1. ______The element curium (Z = 242, A = 96) can be produced by positive-ion bombardment when an alpha particle collides with which of the following nuclei? Recall that a neutron is also a product of this bombardment.
a) b) c) d) e)
2. ______The cesium-131 nuclide has a half-life of 30 years. After 90 years, about 6 g remains. The original mass of the cesium-131 sample is closest to
a) 30 g b) 40 g c) 50 g d) 60 g e) 70 g
3. ______The atomic particle having a mass of 0 amu and a charge of -1 is
a) an electron b) a neutron c) an alpha particle d) a proton e) none of these
4. ______True or false? Nuclear fusion uses heavy nuclides such as as fuel.
a) True b) False
5. ______Which of the following statements is/are true?
- John Dalton provided the first experimental support for the atom.
- Ernest Rutherford proved the existence of a nucleus by shooting positively charged particles at a thin gold-foil sheet.
- J. J. Thompson proved that electrons travel in elliptical orbits around the nucleus.
- Energy in an atom is quantized, so when electrons fall to their ground state, white light can be observed.
a) I, II b) I, III c) I, II, III d) II, IV e) All of the above statements (I – IV) are correct.
6. ______Which atomic particle determines the chemical behavior of an atom?
a) proton b) electron c) neutron d) nucleus e) none of these
7. ______An element's most stable ion forms an ionic compound with chlorine having the formula XCl2. If the ion of element X has a mass of 89 and 36 electrons, what is the identity of the element, and what is the neutron count?
a) Kr, 53 neutrons b) Kr, 55 neutrons c) Se, 55 neutrons d) Sr, 51 neutrons e) Rb, 52 neutrons
8. Identify an element for each of the following situations:
a. The heaviest noble gas
b. The transition metal that has 24 electrons as a +3 ion
c. The halogen in the third period
d. The alkaline earth metal that has 18 electrons as a stable ion
9. ______How many electrons are present in a tin atom with a mass number of 120?
a) 50 b) 120 c) 170 d) 70 e) 6.02 1023
10. ______The number of protons in the nucleus of an atom is called its
a) mass number b) valence c) isotope number d) atomic number e) none of these
11. ______Which of the following elements is an alkali metal?
a) Ca b) Cu c) Fe d) Na e) Sc
12. ______Which of the following elements is most similar to chlorine?
a) H b) He c) Na d) Hg e) Br
13. ______The form of EMR that has more energy per photon than ultraviolet rays but less energy per photon than gamma rays is
a) microwaves b) radio waves c) X rays d) infrared rays e) none of these
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14. ______Which color of visible light has the most energy per photon?
a) violet b) blue c) green d) yellow e) red
15.______When an electron in the ground state absorbs energy, it goes to a(n) ______state.
a) excited b) lower c) frenetic d) ionic e) stable
16.______The probability map for an electron is called
a) an orbit b) a photon c) an orbital d) an electron configuration e) none of these
17.______As the principal energy level increases in an atom's orbitals, the average distance of an electron energy level from the nucleus ______.
a) increases b) decreases c) stays the same d) varies e) none of these
18.______A given set of f orbitals consists of ______orbital(s).
a) 1 b) 3 c) 5 d) 7 e) 9
19.______The maximum number of electrons allowed in the p sublevel of the third principal level is
a) 1 b) 2 c) 3 d) 6 e) 8
20.______The maximum number of electrons allowed in the fourth energy level is
a) 2 b) 4 c) 8 d) 18 e) 32
21.______Phosphorus has how many electrons in its outermost principal energy level?
a) 1 b) 2 c) 3 d) 5 e) 15
22.______The number of unpaired electrons in a nitrogen atom is
a) 1 b) 2 c) 3 d) 4 e) 5
23.______When moving down a group (family) in the periodic table, the number of valence electrons
a)remains constant; b) increases by 2 then 8 then 18 then 32; c) doubles with each move
d)decreases regularly; e) changes in an unpredictable manner
24.______1s22s22p63s23p64s23d7 is the electron configuration for which of the following atoms?
a) Ca b) Fe c) Cr d) Ar e) Co
25.______The electron configuration for manganese is
a) [Ar] 3d7 b) 1s22s22p63s13d6 c) [Ar] 4s23d5 d) 1s22s22p63s23d4 e) [Ar] 4s24p5
26.______The element with the electron configuration [Kr] 5s24d105p3 is
a) As b) Sb c) Nb d) Pr e) none of these
27.______Which of the following is ranked in order of largest to smallest atomic radius?
a) Rb > Mn > S > Ge > F
b) F > S > Ge > Mn > Rb
c) Mn > Rb > F > S > Ge
d) Rb > Ge > Mn > F > S
e) Rb > Mn > Ge > S > F
28.______Which of the following atoms has the highest ionization energy?
a) Na b) Mg c) Si d) P e) Cl
29.______Which of the following has the smallest atomic radius?
a) N b) F c) Br d) Cl e) S
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30.______Order the elements S, Cl, and F in terms of increasing ionization energy.
a) S, Cl, F b) Cl, F, S c) F, S, Cl d) F, Cl, S e) S, F, Cl
31.______Which of the following bonds does nothave a dipole moment?
a) N-H b) O-H c) F-H d) H-H e) S-H
32.______How many lone pairs of electrons are in the Lewis structure for ammonia, NH3?
a) 0 b) 1 c) 2 d) 3 e) 4
33.Draw the Lewis structure for NI3.
34.______Which of the following molecules are polar? (Check all that apply.)
a) CH3OH b) CH4 c) H2O d) C2H6
35.______Which of the following species exhibit hydrogen bonding? (Check all that apply.)
a) HBr b) NO3– c) H2O d) SF4 e) KrCl4 f) I3–
Consider the following compounds:
CO NH3 CO2 CH4 H2
36.______Which compound has the highest boiling point?
a) CO b) NH3 c) CO2 d) CH4 e) At least two of the above compounds have equally high boiling points.
37.______Which of the following has the highest melting temperature?
a) H2O b) CO2 c) S8 d) MgF2 e) P4
38.______The mostelectronegative element of those listed is
a) Rb b) Cs c) Fr d) K e) Li
39.______Which of the following statements about the periodic table is false?
a) Elements in the same column have similar reactivities because their valence electrons tend to be located in the same types of orbitals.
b) A series of ions that are isoelectronic must have the same electron configuration.
c) The atomic size of the elements increases going across a period from left to right because the number of electrons increases, so they are located further from the nucleus.
d) It takes more energy to remove an electron from lithium than from cesium because the valence electrons in lithium are located closer to the nucleus.
e) Fluorine is the most electronegative element due to its size and nuclear charge.
40.______The correct name for LiCl is
a) lithium monochlorided) lithium chloride
b)lithium(I) chloridee) monolithiummonochloride
c)monolithium chloride
41.______The correct name for FeO is
a) iron oxide b) iron(II) oxide c) iron(III) oxide d) iron monoxide e) iron(I) oxide
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42.______What is the formula for sulfur trioxide?
a) SO b) SO2 c) SO3 d) S3O e) S3O3
43.______The correct name for P2O5 is
a)phosphorus(II) oxide b)phosphorus(V) oxide c)diphosphorus oxide
d) diphosphorus pentoxide e) phosphorus pentoxide
44.______Titanium(IV) oxide has the formula
a) Ti4O b) TiO4 c) Ti(IV)O d) TiO2 e) Ti4O2
45.______The correct name for an aqueous solution of H2SO4 is
a) sulfurous acid b) hydrosulfurous acid c) sulfuric acid d) hydrosulfuric acid
e) none of these
46.______The correct name for an aqueous solution of H3PO4 is
a)hydrophosphoric acidd)hydrophosphorus acid
b)phosphorous acide)phosphoric acid
c)phosphate acid
47.______The correct name for an aqueous solution of HCl is
a) chloric acid b) hydrochloric acid c) hypochloric acid d) hypochlorous acid e) perchloric acid
48.______The formula for the compound formed from ammonium and sulfate ions is
a) NH4SO4 b) (NH4)2SO4 c) NH4(SO4)2 d) (NH4)3SO4 e) none of these
49.______The name for the acid HNO2 is
a) nitrous acid b) nitric acid c) hydronitrous acid d) hydronitric acid e) hydrogen nitrite acid
50.______The name for Al(OH)3 is
a)aluminum(III) hydroxided) monaluminumtrihydroxide
b)aluminum trihydroxide e) aluminum(I) hydroxide
c)aluminum hydroxide
51.______The name for Ba(NO3)2 is
a) barium dinitrate b) barium(II) nitrate c) barium nitrite
d) barium(I) nitrate e) barium nitrate
52.______True or false? The greater the difference in electronegativity between two bonded atoms, the more polar the bond.
a) True b) False
53.______Rank the following bonds from least polar to most polar:
Si-ClP-ClMg-ClS-Cl
a)S-Cl, P-Cl, Mg-Cl, Si-Cld)Mg-Cl, S-Cl, P-Cl, Si-Cl
b)P-Cl, S-Cl, Si-Cl, Mg-Cle)S-Cl, P-Cl, Si-Cl, Mg-Cl
c)Mg-Cl, Si-Cl, P-Cl, S-Cl
54.______Which of the following bonds would be the most polar without being considered ionic?
a) Mg-O b) C-O c) O-O d) Si-O e) N-O
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55.______A sample of platinum is found to have 3.42% Pt-193, 0.70% Pt-197 and 95.88% Pt-195. Calculate the average atomic mass of this element.
a) 193.44 b) 195.08c) 195.00d) 194.95
56. ______Which type of electromagnetic energy has the shortest wave length?
- Visible light b. Radio waves c. Ultraviolet (UV) radiation d. Gamma radiation
57.______The mathematical equation c= λf means that as the wavelength (λ) increases, the frequency (f) decreases. The equation E = hf means that as frequency increases, energy increases. Using this information and the reference tables, which color of visible light has the least energy?
a. Red b. Yellow c. Green d. Violet e. Orange
58.______Using the Bohr model diagram, if an electron drops from the shells, n=6 to n=2, what type of electromagnetic radiation is emitted?
a. Ultraviolet (UV) b. Visible c. Infrared (IR) d. Radiowaves e. Gamma
59.______This equation represents the alpha decay of U-238: 238U 4He + X
92 2
What is the mass number of the element represented by X?
A) 88; B) 228; C) 90; D) 242; E) 234
60.______What is the oxidation number (charge) of potassium in K2CrO4?
A) +1; B) +2; C) +4; D) +6; E) -2
61.______Consider these four element – Fe, Ge, Rb, O. Arrange them in order of increasingelectronegativity.
A) Rb < Fe < Ge < O; B)Ge < Fe < Rb < O; A) Rb < Ge < O < Fe;
D) O < Ge < Fe < Rb; E) Rb < O < Fe < Ge
62.______Which of the following sets of quantum numbers is NOT valid?
a. (1, 0, 0, +½)b. (2, 2, 0, -1/2)c. (3, 2, -1, +1/2)d. (4, 1, 0, -1/2)
63.______Which of the following is the correct set of quantum number for the 21st electron of Xenon?
a. (6, 2, 1, -1/2)b. (4, 2, -2, +1/2)c. (3, 2, -2. +1/2)d. (5, 1, 1, -1/2)
64.______How many total atoms are in exactly 1.000 microgram of pure, distilled water?
65.______How many grams of sodium chloride would you need in order to have the same number of sodium ions as you have in 43.9 grams of sodium peroxide?
66.______How many liters of gas do you have if you have 80.0 grams of carbon dioxide?
(Assume STP)
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67.______If you had the same volume of gas at the same STP, but the gas is changed to helium gas, how many more moles of gas would you have?
68.______A certain compound is composed of 1.505 x 1023 atoms of potassium, 13.0 grams of chromium, and 0.875 moles of oxygen. What is the simplest whole number mole ratio of elements in this compound?
69.______How many ions (total of both cations and anions) are there in 80.5 grams of barium phosphate?
70. (a) ______Calculate the density of: (a) an object that has a mass of 3.9 g and a volume of 7.2 mL and (b) an object with a mass of 250.0 g that when placed in a graduated cylinder containing21.6 mL caused the water level to rise to 59.7 mL.
(b) ______
71. Fill in the chart below.
Element / Electron Configuration / Noble Gas Configuration / Lewis Dot Structure / # Half-filled orbitalsCobalt
1s22s22p63s23p64s23d104p4
[Ne] 3s23p3
72. Which of the following: (circle the correct answer)
A. Has the greatest electronegativity: Na or Li K or Ca F or Ne C or Si
B. Has the greatest ionization energy: Ca or Mg Rb or Cs P or S Cl or F
C. Has the smallest atomic radius: Ca or Mg Rb or Cs P or S Cl or F
D. Is the most reactive: Al or Sr K or Mg P or O Ne or Si
Answer Key
1.e
2.c
3.a
4.b
5.a
6.b
7.d
8.a. Rn
b. Co
c. Cl
d. Ca
9.a
10.d
11.d
12.e
13.c
14.a
15.a
16.c
17.a
18.d
19.d
20.e
21.d
22.c
23.a
24.e
25.c
26.b
27.e
28.e
29.b
30.a
31.d
32.b
33.
34.a, c
35.c
36.b
37.d
38.e
39.c
40.d
41.b
42.c
43.d
44.d
45.c
46.e
47.b
48.b
49.a
50.c
51.e
52.a
53.e
54.d
55.d
56.d
57.a
58.b
59.e
60.a
61.a
62.b
63.c
64.How many total atoms are in exactly 1.000 microgram of pure, distilled water?
1.000 x 10-6 g cpd.(1 mol cpd./18.0 g. cpd.)(3 mol atoms / 1 mol cpd.)(6.02 x 1023 atoms/1 mol atoms)
= 1.00 x 1017 atoms total
65.How many grams of sodium chloride would you need in order to have the same number of sodium ions as you have in 43.9 grams of sodium peroxide?
1 mol Na2O2 2 mol Na 1 molNaCl 58.5 g NaCl
43.9 g Na2O2 x ------x ------x ------x ------= 65.9 g NaCl
78.0 g Na2O2 1 mol Na2O2 1 mol Na 1 molNaCl
66.How many liters of gas do you have if you have 80.0 grams of carbon dioxide? (Assume STP)
80.0 g CO2 (1 mol CO2 / 44.0 g CO2) (22.4 L CO2 / 1 mol CO2) = 40.7 L
67.If you had the same volume of gas at the same STP, but the gas is changed to helium gas, how many more moles of gas would you have?
no more moles; 22.4 L per mole is a constant @STP for any gas
68.A certain compound is composed of 1.505 x 1023 atoms of potassium, 13.0 grams of chromium, and 0.875 moles of oxygen. What is the simplest whole number mole ratio of elements in this compound?
K 1.505 x 1023 atoms / 6.02 x 1023 = 0.250 mol K
Cr 13.0 g / 52.0 g/mol = 0.250 mol Cr & 0.875 mol O
K : Cr : O => 0.250 : 0.250 : 0.875 (divide all by 0.250) = 1: 1: 3.5 => 2 : 2 : 7
K2Cr2O7 or potassium dichromate
69. How many ions (total of both cations and anions) are there in 80.5 grams of barium phosphate?
80.5 g cpd 1 molcpd 5 mols ions 6.02 x 1023 ions
x ------x ------x ------= 4.03 x 1023 ions
601.9 g cpd 1 molcpd 1 mols ions
70. (a) 0.54 g/mLCalculate the density of: (a) an object that has a mass of 3.9 g and a volume of 7.2 mL and (b) an object with a mass of 250.0 g that when placed in a graduated cylinder containing21.6 mL caused the water level to rise to 59.7 mL.
(b) 6.56 g/mL(a) D = M / V = (3.9 g) / (7.2 mL) = 0.54 g/mL
(b) D = M / V = 250.0 g / (59.7mL – 21.6 mL) = 6.56 g/mL
71. Fill in the chart below.
Element / Electron Configuration / Noble Gas Configuration / Lewis Dot Structure / # Half-filled orbitalsCobalt / 1s22s22p63s23p64s23d7 / [Ar] 4s23d7 / / 3
Selenium / 1s22s22p63s23p64s23d104p4 / [Ne] 3s23p3 / / 2
Phosphorous / 1s22s22p63s23p3 / [Ne] 3s23p3 / / 3
72. Which of the following: correct answer is BOLDED
A. Has the greatest electronegativity: Na or Li K or Ca F or Ne C or Si
B. Has the greatest ionization energy: Ca or Mg Rb or Cs P or S Cl or F
C. Has the smallest atomic radius: Ca or Mg Rb or Cs P or S Cl or F
D. Is the most reactive: Al or Sr K or Mg P or O Ne or Si