GENERAL CHEMISTRY I – MCQ - FINAL EXAMINATION

Contents ( 7 Parts / 10 Questions each )

Matter and Measurement............................................................................................................ 1
Atomic structure.......................................................................................................................... 6
Electronic structure of atoms.....................................................................................................9
Periodic properties of elements............................................................................................... 12
Basic concept of chemical bonding........................................................................................ 15
Molecular Geometry and Bonding Theory.............................................................................. 18
Chemical Reaction.....................................................................................................................22

Matter and Measurement

1. In the following list, only ____ is not an example of matter.

A) the Earth
B) dust
C) sand
D) light

2. In the following list, which mixture is considered homogeneous?

A) Vinegar
B) Water in the sewer
C) Air in Hanoi
D) Egg yolk in a boiling stove

3. Given various phenomena, which one is not classified as a physical change?

A) The sky starts raining.
B) Iron ores are molten for forging.
C) Some parts of a ship got rusted.
D) Cubes of sugar in water makes the water become sweet.
4. Precision refers to __________.
A) how close a measured number is to other measured numbers
B) how close a measured number is to the true value
C) how close a measured number is to the calculated value
D) how close a measured number is to zero

5. Accuracy refers to __________.

A) how close a measured number is to zero
B) how close a measured number is to the calculated value
C) how close a measured number is to other measured numbers
D) how close a measured number is to the true value
E) how close a measured number is to infinity

6. Which kind of thermal process is this

A) Endothermic
B) Exothermic

7. Which transformation describes accurately one of the two phase transformations

between the solid and the gas phase.
A) Condensation
B) Melting
C) Evaporation
D) Sublimation
 8. Given the following chart, what is the state of CO2 at 100 atm and –200C

A) Solid
B) Liquid
C) Gas
D) Supercritical fluid

9. Following the illustration, this is a ________

A) physical change.
B) biological change.
C) chemical change.
D) change we cannot determine.
10. In the following list, only _______ is classified as an element.
A) a bronze medal.
B) water
C) sulfur powder
D) fresh air

Answers for Matter and Measurement

1.D 2.A 3.C 4.A 5.D 6.A 7.D 8.B 9.C 10.C
Atomic structure

1. In Dalton’s Atomic theory, which clue(s) was not exact in modern theory
A)All matter is composed of extremely small particles called atoms
B)Atoms of a given element are identical in size, mass, and other properties
C)Atoms cannot be subdivided, created, or destroyed
D)Atoms of different elements can combine in simple whole number ratios to form
chemical compounds.
E)In chemical reactions, atoms are combined, separated, or rearranged

2. J.J Thompson’s experiment with He showed

What will happen to the value of Δx– , compared to that for the hydrogen gas? Assume
applied voltages are the same
A)Increase
B)Decrease
C)Stay the Same
3. In Rutherford’s experiment

Why did very few of these particles bounce back?

A)Because the atoms are bigger than the beam
B)Because the nucleus of the atoms are very small
C)Because the nucleus of the atoms have the same charge
D)Because the beam fired exactly through hole between atoms

4. In which group, elements are found as monatomic species in nature?

A)IVA
B)VA
C)VIIIA
D)IA
E)VIIA
G)IIA

5. What are the mass of those Hidro’s isotopes: D, T, H

A)1,2,3
B)1,3,2
C)3,1,2
D)2,3,1

6. Above those elements which element have most neutrons : (a)samarium( Sm) -154,
(b) lutetium( Lu) -177, (c) bismuth( Bi) -185
A) a
B) b
C) c
7. The compound Na3X(C2O4)3 the number of protons is 191, what X element is?
A)Cu
B)Co
C)Fe
D)Cr

8. Mass of Fe is 18.2224g .Find the number of atoms. (Approximate)

A)1.8459 x 1023
B)19.589 x 1022
C)19.203 x 1024
D)1.9500 x 1023

9. Find the average mass of Cu which 63Cu 69.15% and 65Cu 30.85%
A)64
B)63.617
C)63
D)64.312

10. An atom of 18O contains __________ neutrons.

A)18
B)16
C)10
D) 8

Answers for Atomic Structure

1.B,C 2.C 3.B,C 4.C 5.D 6.B 7.C 8.B 9.B 10.C
Electronic structure of atoms
You can choose more than 1 answer.

1. The principal quantum number of the first d subshell is ______________

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

2. Which orbital has a higher ionization energy, one with n=3 or n=2?
A) We cannot determine accurately
B) n=2
C) The energy is identical
D) n=3

3. At the principal quantum number n=3, what type of orbital(s) can be found?
A) 3s
B) 3d
C) 3p
D) 3f

4. Given the following quantum numbers sets, which one is/are correct?
A) n=2, l=1, ml=0, ms=0
1
B) n=2, l=1, ml=0, ms= 2
−1
C) n=2, l=1, ml=0, ms= 2
1
D) n=1, l=2, ml=0, ms= 2
 5. Of the following transitions in the Bohr hydrogen atom, the __________ transition
results in the emission of the highest-energy photon.
A) n = 1 → n = 6
B) n = 6 → n = 1
C) n = 6 → n = 3
D) n = 3 → n = 6

6. Calculate the energy (J) change associated with an electron transition from n = 2 to
n = 5 in a Bohr hydrogen atom
A) 6.5 × 10-19
B) 5.5 × 10-19
C) 8.7 × 10-20
D) 4.6 × 10-19

7. In a px orbital, the subscript x denotes the __________ of the electron.

A) energy
B) spin of the electrons
C) axis along which the orbital is aligned
D) size of the orbital

8. Hund's rule states that______________

A) Every orbital in a sublevel is singly occupied before any orbital is doubly occupied.
B) All of the electrons in singly occupied orbitals have the same spin (to maximize spin).
C) Two atoms attract each other (create a covalent bond) by sharing a pair of electrons.
D) Only two electrons can occupy the same orbital.
9. What is the correct electronic configuration of Copper (Cu)?
A) 1s22s22p63s23p63d104s1
B) 1s22s22p63s23p63d94s2
C) 1s22s22p63s23p63d64s2
D) 1s22s23s23p10

10. Which two elements have the same ground-state electron configuration?
A) Pd and Pt
B) Cu and Ag
C) Cl and Ar
D) No two elements have the same ground-state electron configuration.

Answers for Electronic structure of atoms

1.C 2.B 3.A,B,C 4.B,C 5.B 6.D 7.C 8.A,B 9.A 10.D
Periodic properties of elements

1. Which one of the following elements is most likely to lose electrons when forming
an ion?
A) Co
B) As
C) Cl
D) Xe

2. Which pair of elements would you expect to exhibit the greatest similarity in their
physical and chemical properties?
A) Ga – Ge
B) As – Se
C) He – Ne
D) C – S

3. The scientists are planning on synthesizing Unbinilium – The 120th element. Which
pair of elements has the most potential for this process?
A) Cf – Ti
B) Cm – Cr
C) Cm – V
D) Cf – Sc

4. Approximately, the Effective nuclear charge (Zeff) of the Na nuclei to its 3s

11

electron should be:

A) 10
B) 11
C) 1
D) +1 (Slightly larger than 1)
 5. Regarding the 11Na atom, which of the following statements is correct?
A) Effective nuclear charges to 3s and 2s electrons are identical
B) There is no effective nuclear charge to 2s electron (but only to 3s electron)
C) Effective nuclear charge to 3s electron is smaller than that to 2s electron
D) Effective nuclear charge to 3s electron is greater than that to 2s electron

6. Arrange following ions in order of increasing ionic radius:

O2-, F-, Na+, Mg2+, Al3+
A) O2- < F- < Na+ < Mg2+ < Al3+
B) Na+ < Mg2+ < Al3+ < O2- < F
C) Al3+ < Mg2+ < Na+ < O2- < F-
D) Al3+ < Mg2+ < Na+ < F- < O2-

7. Germanium (Z=32) usually has oxidation states of +2 and +4 , but it can also have
oxidation states of +1 and +3 in compounds such as Ge2Cl6 or in certain oxides. The
electron configuration of neutral germanium is
Ge: [Ar]3d104s24p2
Find the electron configuration of Ge3+
A) [Ar]3d104s1
B) [Ar]3d74s24p2
C) [Ar]3d94s2
D) [Ar]3d84s1

8. The atomic radius of main-group elements generally increases down a group

because __________.
A) effective nuclear charge increases down a group
B) effective nuclear charge zigzags down a group
C) the principal quantum number of the valence orbitals increases
D) both effective nuclear charge increases down a group and the principal quantum
 9. Which of the following reactions would present correctly the second ionization of
Mg?
A) Mg(g)+ → Mg(g)2+ + 1e
B) Mg(g) → Mg(g)2+ + 2e
C) Mg(s) → Mg(s)2+ + 2e
D) Mg(s)+ → Mg(s)2+ + 1e

10.The element Gallium has different energy requirements for each successive
ionization. Which of the given energy requirement orders is the most accurate?
A) I1 > I2 > I3 >> I4
B) I1 > I2 > I3 > I4
C) I1 < I2 < I3 << I4
D) I1 < I2 < I3 < I4

Answers for Periodic properties of elements

1.A 2.C 3.B 4.D 5.C 6.C 7.A 8.B 9.A 10.C
Basic concept of chemical bonding

1. Which groups of elements/molecules have the same type of bonding in all of their
compositions?
A) HCl, NaCl, MgSO4, CaCO3
B) Cl2, H2O, H2O2, H3PO4
C) Fe, Cu, Al, Si
D) Al(NO3)3, H2SO4, HNO3, FeSO4

2. How many valence electrons does Bromine (Br) have?

A) 8
B) 6
C) 7
D) 5

3. Following the octet rule, the Oxygen atom will ____ electrons until it has ____
valence electrons.
A) receive 2 – 8
B) give 2 – 8
C) give 2 – 0
D) receive 2 – 0

4. Which element/ion has the electron configuration the same as of a noble gas?
A) Mg+
B) Fe2+
C) O2-
D) F

5. The ion ICI4- has __________ valence electrons.

A) 34
B) 36
C) 28
D) 8
6. What is the correct order of increasing lattice energy of the following ionic
compounds ( NaF, CsI, CaO )
A) NaF < CsI < CaO
B) CaO < CsI < NaF
C) CsI < NaF < CaO

7. Select the shortest chemical bond out of all the given ones.
A) N–N
B) N=N
C) N≡N
D) C–C

8. Given the bond enthalpies below, what is the correct ∆H of the following reaction?

Bond C–H C–Cl Cl–Cl H–Cl

Bond enthalpy (KJ/mol) 413 328 242 431

Reaction:

A) + 104 KJ/mol
B) + 68 KJ/mol
C) – 68 KJ/mol
D) – 104 KJ/mol
 9. A valid Lewis structure of ________ cannot be drawn without violating the octet rule.
A) NF3
B) IF3
C) PF3
D) SO42-

10. Given the following figure, the bond length between each S–O bonds are ____.
There can be up to ____ resonance structures of the given compound.

A) Identical – 4
B) Different – 6
C) Identical – 6
D) Different – 4

Answers for Basic concept of chemical bonding

1.B 2.C 3.A 4.C 5.B 6.C 7.C 8.B 9.B 10.C
Molecular Geometry and Bonding Theory

1. According to VSEPR theory, if there are four electron domains with one lone pair in
the valence shell of an atom, they will be arranged in a(n) __________ geometry.
A) octahedral
B) linear
C) trigonal pyramidal
D) trigonal planar

2. The S–C–S bond angle in the CS2 molecule is approximately __________.

A) 90°
B) 109.5°
C) 120°
D) 180°
 3. The molecular geometry of the right-most carbon in the molecule below is
__________.

A) trigonal planar
B) trigonal bipyramidal
C) tetrahedral
D) T-shape

4. In which of these molecules or ions does the presence of non-bonding electron

pairs produce an effect on molecular shape?
A) SiH₄
B) PF₃
C) CS2
D) HCN

5. For which of the molecules is the molecular geometry (shape) the same as the
VSEPR electron domain arrangement (electron domain geometry)?
(i) PCl3 (ii) CCl4 (iii) TeCl4 (iv) XeF4 (v) SF6
A) (v) only
B) (i) and (ii)
C) (i) and (iii)
D) (ii) and (v)
6. Of the molecules below, only __________ is polar.
A) SF6
B) CH4
C) NH3
D) CO2

7. According to valence bond theory, which orbitals overlap in the formation of the
bond in HI?
A) 1s on H and 4p on I
B) 1s on H and 5s on I
C) 2s on H and 5p on I
D) 1s on H and 5p on I

8. The electron-domain geometry of a nitrogen-centered compound is trigonal

pyramidal. The hybridization of the central nitrogen atom is __________.
A) sp
B) sp2
C) sp3
D) sp3d

9. Based on molecular orbital theory, the bond order of the N–N bond in the N22+ ion is
__________.
A) 0
B) 3
C) 2
D) 1/2
 10. In molecular orbital theory, the σ1s orbital is __________ and the σ1s* orbital is
__________ in the H2 molecule.
A) filled – empty
B) filled – half-filled
C) half-filled – filled
D) empty – filled

Answers for Molecular Geometry and Bonding Theory

1.C 2.D 3.A 4.B 5.D 6.C 7.D 8.C 9.C 10.A
Chemical Reaction

1. While manufacturing a DIY light-bulb, Linh decides to use electricity produced from
an aqueous solution. Which given solution is the best choice here so that the
light-bulb will work the brightest?
A) NaCl
B) CH3COOH
C) K2SO3
D) HF

2. What is the CORRECT net ionic equation of the reaction between KHCO3 and
H2SO4?
A) H+ + HCO3- → CO2 + H2O
B) 2Na+ + SO42- → Na2SO4
C) H+ + OH- → H2O
D) 2K+ + HCO3- + H+ + SO4 → K2SO4 + CO2 + H2O

3. What is the oxidation number of N in NH4Cl?

A) 0
B) –5
C) +3
D) –3

4. Out of all the given reactions, which one is not a Redox reaction?

A) Fe + CuSO₄ → FeSO₄ + Cu
B) NaOH + H₂SO₄ → Na₂SO₄ + H₂O
C) 3Cu + 8HNO₃ → 3Cu(NO₃)₂ + 2NO + 4H₂O
D) H₂ + Cl₂ → 2HCl
 5. A Copper ingot is presented to have some Iron particles on it. Which given solution
is the best choice to cleanse off all the Iron on it with all the proper conditions?
A) AgNO3
B) AlCl3
C) NaOH
D) CuSO4

6. When the farmers want to use fertilizers for the crops, why shouldn’t they use Urea
fertilizer (NH₂CONH₂) with Lime (CaO) together?
A) Because the crops will die in such acidic soil by fertilizing too much Urea.
B) Because Calcium Hydroxide is toxic to the crops.
C) Because a large amount of Nitrogen nutrition could be lost in the form of Ammonia.
D) Because Urea is not a good fertilizer for the crops.

7. Which compound out of all the given ones here is a weak electrolyte.

A) NaOH
B) C2H5OH
C) BaCl2
D) H2SO4

8. For the next experiment the class will need 400 mL of 0.1 M MgCl2. There is a
bottle of 2.0 M MgCl2 and a bottle of distilled Water. How much of the 2.0 M solution
do we need?
A) 10 mL
B) 20 mL
C) 40 mL
D) 5 mL
 9. If 1 mol C₂H₅OH, 1 mol C₃H₈ and 1 mol CH₃CH₂COCH₃ are completely combusted in
oxygen, which produces the largest number of moles of H₂O?
A) 1 mol C₂H₅OH
B) 1 mol C₃H₈
C) 1 mol CH₃CH₂COCH₃
D) Need more specific figures to calculate

10. How many grams of Na₂SO₄ are required to make 0.350 L of 0.500 M Na₂SO₄?

A) 24.85 g
B) 28.4 g
C) 35.5 g
D) 17.75 g

Answers for Chemical Reaction

1.A 2.A 3.D 4.B 5.D 6.C 7.B 8.B 9.C 10.A