Worksheetschem fall final review
Total questions: 102
Worksheet time: 51mins
Name
Class
Date
1.
Which type of bond forms when electrons are shared between atoms?
a)
Ionic
b)
Metallic
c)
Covalent
d)
Hydrogen
2.
Which pair of elements would form an ionic bond?
a)
H and O
b)
C and O
c)
Na and Cl
d)
N and H
3.
Which type of bond forms when electrons are shared between atoms?
a)
Ionic
b)
Metallic
c)
Covalent
d)
Hydrogen
4.
Which pair of elements would form an ionic bond?
a)
H and O
b)
C and O
c)
Na and Cl
d)
N and H
5.
Which molecule is nonpolar?
a)
H–Cl
b)
H₂O
c)
NH₃
d)
H₂
6.
Hydrogen bonding occurs between…
a)
Hydrogen atoms inside the same molecule
b)
Hydrogen and a metal
c)
Hydrogen and highly electronegative atoms like N, O, or F in another molecule
d)
Any two atoms that share electrons
7.
Which of the following shows a correct Lewis structure for water?
a)
H–O–H, no lone pairs
b)
H–O–H with two lone pairs on O
c)
O with no electrons
d)
H–H–O
8.
Which element is the most inert (least reactive)?
a)
Ca
b)
Br
c)
Xe
d)
Li
9.
Which group contains the elements with the highest electronegativity?
a)
Alkali metals
b)
Alkaline earth metals
c)
Halogens
d)
Noble gases
10.
Which electron-dot symbol is correct for chlorine?
a)
Cl with 5 dots
b)
Cl with 7 dots
c)
Cl with 8 dots
d)
Cl with 1 dot
11.
Which element has 30 electrons?
a)
Si
b)
P
c)
Zn
d)
Ar
12.
Metals tend to…
a)
Gain electrons and form negative ions
b)
Lose electrons and form positive ions
c)
Gain electrons and form positive ions
d)
Share electrons and form neutral ions
13.
Which subatomic particles are found in the nucleus?
a)
Protons and electrons
b)
Electrons and neutrons
c)
Protons and neutrons
d)
Protons and positrons
14.
The nucleus of an atom is…
a)
Small, dense, and positively charged
b)
Large, empty, and negatively charged
c)
Small, empty, and neutral
d)
Large, dense, and negatively charged
15.
What is the atomic number equal to?
a)
Protons + neutrons
b)
Mass number
c)
Number of protons
d)
Number of electrons in the outer shell
16.
A neutron has…
a)
Charge +1 and mass 1 amu
b)
Charge –1 and mass 1 amu
c)
No charge and mass 1 amu
d)
No charge and no mass
17.
If the nucleus were the size of a baseball, the atom would be the size of…
a)
A softball
b)
A cafeteria
c)
A basketball
d)
A large stadium
18.
Which compound contains a repeating pattern of positive and negative ions?
a)
CO₂
b)
H₂
c)
NaCl(s)
d)
Neon gas
19.
Which statement describes a metal during ionic bonding?
a)
Gains electrons and becomes negative
b)
Shares electrons
c)
Loses electrons and becomes positive
d)
Does not change
20.
How many atoms are in 1.0 mole of He gas?
a)
3 × 10²³
b)
4 × 10²³
c)
6 × 10²³
d)
6 × 10²²
21.
What is the molar mass of Ca(OH)₂?
a)
29 g/mol
b)
34 g/mol
c)
57 g/mol
d)
74 g/mol
22.
How many grams are in 3 moles of CO₂?
a)
12
b)
24
c)
36
d)
132
23.
What must be the same on both sides of a balanced chemical equation?
a)
Number of molecules
b)
Number of atoms of each element
c)
Total number of compounds
d)
Mass number
24.
Which is the correct balanced equation for nitrogen reacting with hydrogen?
a)
N₂ + H → NH₃
b)
N₂ + 3H₂ → 2NH₃
c)
2N + 3H₂ → NH₃
d)
N₂ + 2H₂ → 3NH₃
25.
What is the mole ratio H₂ : NH₃ in the balanced equation N₂ + 3H₂ → 2NH₃?
a)
1 : 3
b)
3 : 2
c)
2 : 3
d)
3 : 1
26.
When balancing equations, you may change…
a)
Subscripts
b)
Chemical symbols
c)
Superscripts
d)
Coefficients
27.
In the balanced form of
Ag₂S + HNO₃ → AgNO₃ + NO + H₂O,
which coefficient comes first?
a)
1
b)
2
c)
3
d)
4
28.
What type of bond forms between a metal and a nonmetal?
a)
Covalent
b)
Metallic
c)
Ionic
d)
Hydrogen
29.
Which molecule is polar?
a)
O₂
b)
CO₂
c)
HCl
d)
N₂
30.
Which compound contains only covalent bonds?
a)
CaCl₂
b)
Li₂O
c)
H₂O
d)
Na₂S
31.
Which situation describes electrons being shared unequally?
a)
Ionic bonding
b)
Nonpolar covalent bonding
c)
Polar covalent bonding
d)
Metallic bonding
32.
Which substance exhibits hydrogen bonding between molecules?
a)
CO₂
b)
CH₄
c)
H₂S
d)
NH₃
33.
Which element has the highest ionization energy?
a)
Lithium
b)
Carbon
c)
Fluorine
d)
Sodium
34.
Elements in the same group have similar…
a)
masses
b)
valence electrons
c)
atomic numbers
d)
nucleus size
35.
Which is the correct electron-dot symbol for oxygen (O)?
a)
O with 2 dots
b)
O with 4 dots
c)
O with 6 dots
d)
O with 8 dots
36.
Which element is a metal?
a)
S
b)
Ne
c)
Mg
d)
Br
37.
Which element is least reactive?
a)
F
b)
Na
c)
Ar
d)
Cl
38.
Which statement about the nucleus is correct?
a)
It contains only electrons
b)
It is small and positively charged
c)
It occupies most of the atom’s volume
d)
It has a negative charge
39.
Which particle has a mass of approximately 1 amu and no charge?
a)
Proton
b)
Electron
c)
Neutron
d)
Positron
40.
If an atom has 17 protons, what element is it?
a)
Cl
b)
S
c)
P
d)
Ar
41.
Most of the atom’s volume is occupied by…
a)
protons
b)
empty space
c)
the nucleus
d)
neutrons
42.
What does the atomic number represent?
a)
Protons + neutrons
b)
Electrons
c)
Protons
d)
Neutrons
43.
What is the charge of an ion that has lost one electron?
a)
–1
b)
–2
c)
+1
d)
+2
44.
Which formula represents an ionic compound?
a)
CO₂
b)
NH₃
c)
HCl
d)
K₂O
45.
How many molecules are in 2 moles of H₂O?
a)
3.01 × 10²³
b)
6.02 × 10²³
c)
1.20 × 10²⁴
d)
3.01 × 10²⁴
46.
What is the molar mass of KBr?
a)
80 g/mol
b)
119 g/mol
c)
167 g/mol
d)
200 g/mol
47.
How many moles are in 16 g of oxygen gas (O₂)?
(Molar mass O₂ = 32 g/mol)
a)
0.25
b)
0.5
c)
1
d)
2
48.
Which equation represents a decomposition reaction?
a)
Ca + Cl₂ → CaCl₂
b)
2H₂O → 2H₂ + O₂
c)
Zn + CuSO₄ → ZnSO₄ + Cu
d)
AgNO₃ + NaCl → AgCl + NaNO₃
49.
Which is the correct balanced form of:
Fe + O₂ → Fe₂O₃
a)
Fe + O₂ → Fe₂O₃
b)
2Fe + O₂ → Fe₂O₃
c)
4Fe + 3O₂ → 2Fe₂O₃
d)
Fe + 3O₂ → 2Fe₂O₃
50.
What is the mole ratio Fe : O₂ in the balanced equation above?
a)
4 : 3
b)
3 : 4
c)
2 : 1
d)
1 : 2
51.
When balancing a chemical equation, you may adjust the…
a)
subscripts
b)
chemical symbols
c)
coefficients
d)
charges on ions
52.
Chemical equations are balanced to show the conservation of…
a)
mass
b)
charge
c)
volume
d)
energy
53.
Which pair of elements will form a covalent bond?
a)
K and Br
b)
Mg and O
c)
S and O
d)
Li and F
54.
Ionic bonds occur when atoms…
a)
share electrons
b)
transfer electrons
c)
split electrons equally
d)
create metallic lattices
55.
Which molecule is polar?
a)
CO₂
b)
H₂
c)
HF
d)
Cl₂
56.
What type of intermolecular force holds one water molecule to another?
a)
Ionic bond
b)
Metallic bond
c)
Hydrogen bond
d)
Covalent bond
57.
Which structural formula shows a nonpolar molecule?
a)
H–Cl
b)
H–F
c)
H–N–H
d)
O=O
58.
Which element is most reactive in Group 17 (halogens)?
a)
Iodine
b)
Bromine
c)
Fluorine
d)
Chlorine
59.
Metals are characterized by…
a)
high electronegativity
b)
low ionization energy
c)
forming negative ions
d)
having completely filled shells
60.
Which electron-dot diagram shows sulfur (S)?
a)
S with 2 dots
b)
S with 6 dots
c)
S with 8 dots
d)
S with 1 dot
61.
Which element has 5 valence electrons?
a)
B
b)
N
c)
Ne
d)
Mg
62.
Which pair are both metalloids?
a)
Si and Ge
b)
Na and K
c)
S and P
d)
H and He
63.
What is the charge of a proton?
a)
–1
b)
0
c)
+1
d)
+2
64.
Which particle has almost no mass?
a)
Proton
b)
Electron
c)
Neutron
d)
Alpha particle
65.
The nucleus of an atom contains…
a)
electrons only
b)
protons and neutrons
c)
protons and electrons
d)
neutrons only
66.
What is the atomic number of an element equal to?
a)
Protons
b)
Neutrons
c)
Mass number
d)
Protons + neutrons
67.
Most of the volume of an atom is…
a)
electrons
b)
protons
c)
neutrons
d)
nuclear space
68.
Which compound is ionic?
a)
CO
b)
O₂
c)
Na₂O
d)
CH₄
69.
When a nonmetal becomes an ion, it…
a)
loses electrons
b)
becomes positive
c)
gains electrons
d)
becomes metallic
70.
How many moles are in 24 g of carbon (C)?
(Atomic mass = 12 g/mol)
a)
1
b)
2
c)
3
d)
4
71.
What is the molar mass of MgCl₂?
a)
47 g/mol
b)
59 g/mol
c)
71 g/mol
d)
95 g/mol
72.
How many atoms are in 2.0 moles of helium gas?
a)
3.01 × 10²³
b)
6.02 × 10²³
c)
1.20 × 10²⁴
d)
3.01 × 10²⁴
73.
When balancing equations, numbers placed in front of formulas are called…
a)
exponents
b)
subscripts
c)
coefficients
d)
superscripts
74.
Which balanced equation is correct?
a)
2H₂ + O₂ → 2H₂O
b)
H₂ + O₂ → H₂O
c)
H₂ + 2O₂ → H₂O
d)
H + O → HO
75.
In the reaction:
2Na + Cl₂ → 2NaCl
What is the mole ratio of Na : NaCl?
a)
1 : 1
b)
2 : 1
c)
1 : 2
d)
3 : 2
76.
Which equation is balanced?
a)
Fe + O₂ → Fe₂O₃
b)
4Fe + 3O₂ → 2Fe₂O₃
c)
Fe + O₂ → FeO₂
d)
Fe₂ + O₂ → Fe₂O
77.
What can be changed when balancing equations?
a)
Subscripts
b)
Chemical symbols
c)
Coefficients
d)
Charges on ions
78.
Which bond is formed when electrons are transferred?
a)
Covalent
b)
Ionic
c)
Metallic
d)
Hydrogen
79.
Which molecule is nonpolar?
a)
NH₃
b)
H₂O
c)
CO₂
d)
HF
80.
Which pair of atoms will share electrons?
a)
Li and Cl
b)
K and Br
c)
S and Cl
d)
Mg and O
81.
Which type of bond forms between two identical nonmetal atoms?
a)
Ionic
b)
Polar covalent
c)
Nonpolar covalent
d)
Hydrogen
82.
Which compound contains only covalent bonds?
a)
NaCl
b)
CaO
c)
CO₂
d)
MgCl₂
83.
Which element has the lowest electronegativity?
a)
F
b)
O
c)
Na
d)
Cl
84.
Noble gases are considered inert because they…
a)
gain electrons easily
b)
have full valence shells
c)
have low ionization energy
d)
form many compounds
85.
Which element has 4 valence electrons?
a)
C
b)
O
c)
Ne
d)
K
86.
Which pair contains elements from the same group?
a)
Li and Na
b)
N and O
c)
C and Al
d)
He and H
87.
Which element is classified as a metalloid?
a)
Br
b)
Si
c)
Ca
d)
S
88.
Which particle determines the identity of an element?
a)
Neutrons
b)
Electrons
c)
Protons
d)
Nucleus
89.
Which statement about electrons is true?
a)
They are found in the nucleus
b)
They have a mass of 1 amu
c)
They have a negative charge
d)
They are heavier than protons
90.
The mass number of an atom is equal to…
a)
protons + electrons
b)
protons + neutrons
c)
neutrons + electrons
d)
electrons only
91.
Most of an atom’s mass comes from…
a)
electrons
b)
neutrons
c)
protons and neutrons
d)
empty space
92.
Compared to the size of the atom, the nucleus is…
a)
small and dense
b)
large and dense
c)
small and empty
d)
large and hollow
93.
What is the charge of an ion that has gained two electrons?
a)
+2
b)
+1
c)
–1
d)
–2
94.
Which compound is ionic?
a)
CO
b)
HCl
c)
CH₄
d)
LiBr
95.
How many moles are in 6.02 × 10²³ molecules of CO₂?
a)
0.5
b)
1
c)
2
d)
3
96.
What is the molar mass of Al₂O₃?
a)
78 g/mol
b)
102 g/mol
c)
120 g/mol
d)
156 g/mol
97.
How many atoms are in 0.5 moles of neon gas?
a)
1.50 × 10²³
b)
3.01 × 10²³
c)
6.02 × 10²³
d)
1.20 × 10²⁴
98.
Which equation is correctly balanced?
a)
H₂ + Cl₂ → 2HCl
b)
2H₂ + Cl₂ → HCl
c)
H₂ + 2Cl₂ → 2HCl
d)
2H₂ + 2Cl₂ → 2HCl
99.
In the equation:
4Al + 3O₂ → 2Al₂O₃
What is the mole ratio O₂ : Al₂O₃?
a)
4 : 2
b)
3 : 2
c)
2 : 3
d)
1 : 2
100.
When balancing equations, you must never change…
a)
subscripts
b)
coefficients
c)
reactants
d)
products
101.
Which of the following is a synthesis reaction?
a)
2H₂O → 2H₂ + O₂
b)
C + O₂ → CO₂
c)
AgNO₃ + NaCl → AgCl + NaNO₃
d)
Zn + HCl → ZnCl₂ + H₂
102.
The purpose of balancing a chemical equation is to show conservation of…
a)
molecules
b)
mass
c)
energy
d)
volume
100 %
