Unit 4: Bonding (Multiple Choice) Flashcards
Given the equation representing a reaction:
H + H -> H2
What occurs during this reaction?
A) A bond is broken and energy is absorbed.
B) A bond is broken and energy is released.
C) A bond is formed and energy is absorbed.
D) A bond is formed and energy is released.
A bond is formed and energy is released.
Which statement describes the energy changes that
occur as bonds are broken and formed during a
chemical reaction?
A) Energy is absorbed when bonds are both broken
and formed.
B) Energy is released when bonds are both broken
and formed.
C) Energy is absorbed when bonds are broken,
and energy is released when bonds are
formed.
D) Energy is released when bonds are broken, and
energy is absorbed when bonds are formed.
Energy is absorbed when bonds are broken,
and energy is released when bonds are
formed.
Given the balanced equation representing a reaction:
2H2O + energy -> 2H2 +O2
Which statement describes the changes in energy and
bonding for the reactant?
A) Energy is absorbed as bonds in H2O are formed.
B) Energy is absorbed as bonds in H2O are
broken.
C) Energy is released as bonds in H2O are formed.
D) Energy is released as bonds in H2O are broken.
Energy is absorbed as bonds in H2O are
broken.
Krypton atoms in the ground state tend not to bond
with other atoms because their
A) second electron shell contains eight electrons
B) third electron shell contains eighteen electrons
C) innermost electron shell contains two electrons
D) outermost electron shell contains eight
electrons
outermost electron shell contains eight
electrons
What is the number of pairs of electrons shared in a
molecule of N2?
A) 1
B) 2
C) 3
D) 6
3
Which electron-dot diagram represents H2?
A) H.H
B)H:H
.. ..
C) :H.H:
.. ..
D) .. ..
:H:H:
.. ..
H:H
Which property is used to determine the degree of
polarity between two bonded atoms?
A) density
B) electronegativity
C) pressure
D) temperature
electronegativity
What occurs when potassium reacts with chlorine to
form potassium chloride?
A) Electrons are shared and the bonding is ionic.
B) Electrons are shared and the bonding is covalent.
C) Electrons are transferred and the bonding is
ionic.
D) Electrons are transferred and the bonding is
covalent.
Electrons are transferred and the bonding is
ionic.
Which formulas represent one ionic compound and
one molecular compound?
A) N2 and SO2
B) Cl2 and H2S
C) BaCl2 and N2O4
D) NaOH and BaSO4
BaCl2 and N2O4
Element X reacts with chlorine to form an ionic
compound that has the formula XCl2. To which
group on the Periodic Table could element X belong?
A) Group 1
B) Group 2
C) Group 13
D) Group 15
Group 2
A substance conducts electricity in the liquid phase
but not in the solid phase. This substance can be
classified as
A) covalent
B) ionic
C) metallic
D) molecular
ionic
The table below shows properties of two compounds at standard pressure.
Which statement classifies the two compounds?
A) Both compounds are ionic.
B) Both compounds are molecular.
C) Compound 1 is ionic, and compound 2 is molecular.
D) Compound 1 is molecular, and compound 2 is ionic.
Compound 1 is ionic, and compound 2 is molecular.
Which substance has nonpolar covalent bonds?
A) Cl2
B) SO3
C) SiO2
D) CCl4
Cl2
A molecular compound is formed when a chemical
reaction occurs between atoms of
A) chlorine and sodium
B) chlorine and yttrium
C) oxygen and hydrogen
D) oxygen and magnesium
oxygen and hydrogen
Which characteristic is a property of molecular
substances?
A) good heat conductivity
B) good electrical conductivity
C) low melting point
D) high melting point
low melting point
Which compound has both ionic and covalent
bonds?
A) CO2
B) CH3OH
C) NaI
D) Na2CO3
Na2CO3
Which element consists of positive ions immersed in
a “sea” of mobile electrons?
A) sulfur
B) nitrogen
C) calcium
D) chlorine
calcium
The degree of polarity of a covalent bond between
two atoms is determined by calculating the
difference in their
A) atomic radii
B) melting points
C) electronegativities
D) ionization energies
electronegativities
An atom of which element bonds with an atom of
hydrogen to form the most polar bond?
A) bromine
B) chlorine
C) fluorine
D) iodine
fluorine
Which formula represents an asymmetrical
molecule?
A) CH4
B) CO2
C) N2
D) NH3
NH3
Which statement describes the charge distribution
and the polarity of a CH4 molecule?
A) The charge distribution is symmetrical and
the molecule is nonpolar.
B) The charge distribution is asymmetrical and the
molecule is nonpolar.
C) The charge distribution is symmetrical and the
molecule is polar.
D) The charge distribution is asymmetrical and the
molecule is polar.
The charge distribution is symmetrical and
the molecule is nonpolar.
Which formula represents a polar molecule?
A) O2
B) CO2
C) NH3
D) CH4
NH3
To break a chemical bond, energy must be
A) absorbed
B) destroyed
C) produced
D) released
absorbed
Which quantities must be conserved in all chemical
reactions?
A) mass, charge, density
B) mass, charge, energy
C) charge, volume, density
D) charge, volume, energy
mass, charge, energy
