chemical bonding.....aims

 

 

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aim 1.....what is the relation between bonding and energy? quiz

aim 2.....how can compounds be differentiated? quiz

aim 3.....what are molecular compounds? quiz

aim 4.....how can molecular polarity be determined? quiz

aim 5.....how can the physical properties of substances be explained? quiz

honors

 

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cross-word puzzle

skills students should be able to do

real-world connections


skills students should be able to do

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Words: arbitrary, broken, conductivity, configuration, covalent, decreases, degree, differentiated, electron-dot, electronegativity, intermolecular forces, ionic, molecular polarity, noble, nonmetals, polar, polyatomic, radius, released, symmetrical, transferred 

 

Compounds can be _____________ by their chemical and physical properties. Two major categories of compounds are _____  and molecular (covalent) compounds. Chemical bonds are formed when valence electrons are: ___________ from one atom to another (ionic), shared between atoms (covalent), mobile within a metal (metallic). In a multiple _________ bond, more than one pair of electrons is shared between two atoms. _________   __________can be determined by the shape of the molecule and the distribution of charge. ____________ (nonpolar) molecules include CO2, CH4, and diatomic elements. Asymmetrical (______) molecules include HCl, NH3, and H2O. When an atom gains one or more electrons, it becomes a negative ion and its _______ increases. When an atom loses one or more electrons, it becomes a positive ion and its radius __________. When a bond is ________, energy is absorbed. When a bond is formed, energy is _________. Atoms attain a stable valence electron ____________ by bonding with other atoms. _______ gases have stable valence configurations and tend not to bond. Physical properties of substances can be explained in terms of chemical bonds and _____________  ________. These properties include ___________, malleability, solubility, hardness, melting point, and boiling point. _________ - ____ diagrams (Lewis structures) can represent the valence electron arrangement in elements, compounds, and ions. _____________ indicates how strongly an atom of an element attracts electrons in a chemical bond. Electronegativity values are assigned according to _________ scales. The electronegativity difference between two bonded atoms is used to assess the ________ of polarity in the bond. Metals tend to react with _________ to form ionic compounds. Nonmetals tend to react with other nonmetals to form _________ (covalent) compounds. Ionic compounds containing ___________ ions have both ionic and covalent bonding.

 

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real-world connections

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quiz 1

 

Question #1
Why is hydrogen gas found in nature as a diatomic molecule rather than a monatomic molecule?
[A] Because the potential energy of H2 is greater than 2 atoms of H.
[B] Because the potential energy of H2 is less than 2 atoms of H.
[C] Because the potential energy of H2 is equal to 2 atoms of H.
[D] Because the potential energy of 2 atoms of H is less than H2.

Question #2
What occurs when two oxygen atoms combine to form O2?
[A] A chemical bond is broken, and energy is released
[B] A chemical bond is formed, and energy is absorbed
[C] A chemical bond is broken, and energy is absorbed
[D] A chemical bond is formed, and energy is released

Question #3
Noble gases have unstable valence configurations and tend not to bond.
True
False

Question #4
Atoms attain a stable valence electron configuration of the noble gases by bonding with other atoms.
True
False

Question #5
Which of the following elements has the highest electronegativity?
[A] Cl
[B] Na
[C] S
[D] Mg

Question #6
When iodine gains one electron it
[A] becomes a positive ion with a smaller radius
[B] becomes a negative ion with a larger radius
[C] becomes a positive ion with a larger radius
[D] becomes a negative ion with a smaller radius

Question #7
How many dots would the electron dot-diagram of N+2 have?
[A] 7
[B] 5
[C] 3
[D] 9

Question #8
An atom's electronegativity determines
[A] its charge
[B] its size of atomic radius
[C] its strength of attraction for electrons in chemical bonds
[D] its type of chemical bond

Question #9
How many dots are to be around He in its Lewis structure?
[A] 1
[B] 6
[C] 8
[D] 2

Question #10
Which of the following species has the smallest radius?
[A] C
[B] C+2
[C] C+4
[D] C-4
 

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quiz 2

 

Question #1
Compounds can be differentiated only by their physical properties
True
False

Question #2
Which of the following compounds does not belong to the major categories of compounds?
[A] NaCl
[B] Na
[C] NO
[D] CO

Question #3
What is ionization energy?
[A] The energy required to add an electron.
[B] The energy required to remove an electron.
[C] The energy required to add an ion.
[D] The energy required to remove an ion.

Question #4
Metals tend to react with nonmetals to form covalent compound.
True
False

Question #5
Ionic bonds are formed when
[A] valence electrons are shared between bonded atoms
[B] valence electrons are transferred from one atom to another
[C] all the electrons are shared between bonded atoms
[D] all the electrons are transferred from one atom to another

Question #6
Ionic compounds cannot contain both ionic and covalent bonding.
True
False

Question #7
Which compound contains ionic bonds?
[A] NO
[B] CaO
[C] HCl
[D] CO

Question #8
Which compound contains a covalent bond?
[A] HCl
[B] NaCl
[C] KF
[D] BeO

Question #9
Which compound contains both ionic and covalent bonding?
[A] MgCl2
[B] CO2
[C] KNO3
[D] KI

Question #10
In ionic bonds, nonmetals are most likely to
[A] gain electrons
[B] lose electrons
[C] share electrons
[D] cancel electrons
 

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quiz 3

 

Question #1
When valence electrons are transferred, a covalent bond is formed.
True
False

Question #2
Which is not an identity of the bond formed between 2 hydrogen atoms?
[A] non polar bond
[B] sharring of electrons
[C] single covalent bond
[D] double covalent bond

Question #3
HCl is formed...
[A] when 1 pair of valence electrons is shared, one from the hydrogen atom and one from the chlorine atom.
[B] when 1 pair of valence electrons is shared, none from the hydrogen atom and two from the chlorine atom.
[C] when hydrogen atom give off one valence electron to chlorine atom.
[D] when chlorine atom give off one valence electron to hydrogen atom.

Question #4
Which statement is not true about Cl2 molecule?
[A] 2 valence electrons are shared.
[B] one valence electron from each chlorine atoms are shared.
[C] both chlorine atoms are stable with 8 valence electrons.
[D] one valence electron from each chlorine atoms are transferred.

Question #5
Nonmetals tend to react with other nonmetals to form molecular (covalent) compounds.
True
False

Question #6
In a multiple covalent bond,
[A] only one pair of electrons is shared.
[B] more than one pair of electrons is shared between two atoms.
[C] more than one pair of electrons is shared between four atoms.
[D] more than two pair of electrons is shared between two atoms.

Question #7
How many valence electrons are shared in a double bond?
[A] 2
[B] 6
[C] 4
[D] 8

Question #8
A triple bond is formed when
[A] 1 pair of electrons is shared.
[B] 2 pairs of electrons are shared.
[C] 3 pairs of electrons are shared.
[D] 4 pairs of electrons are shared.

Question #9
What is used to assess the degree of polarity in the bond?
[A] the sum of electronegativity of the two bonded atoms
[B] electronegativity difference of the two bonded atoms
[C] the sum of ionization energy of the two bonded atoms
[D] atomic radius difference of the two bonded atoms

Question #10
Which bond has the highest degree of polarity?
[A] HF
[B] NO
[C] H2
[D] N2
 

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quiz 4

 

Question #1
Molecular polarity can be determined by the
[A] number of protons
[B] number of electrons
[C] distribution of charge
[D] distribution of neutrons

Question #2
The distribution of charge is determined by the use of
[A] electrons
[B] electronegativity
[C] electropositivity
[D] valence shells

Question #3
Symmetrical molecules are
[A] polar
[B] nonpolar
[C] none of the above

Question #4
In CH4, in which direction are the valence electrons being pulled?
Hint: (draw the Lewis structure of CH4)
[A] closer to the H's
[B] closer to the C
[C] in between the H and C
[D] none of the above

Question #5
The distribution of charge is unequal in an asymmetrical molecule.
True
False

Question #6
Which of the following is a nonpolar molecule?
[A] HCl
[B] NH3
[C] CH4
[D] H2O

Question #7
Hydrogen bonding is an example of a
[A] weak intermolecular force
[B] strong intermolecular force
[C] weak covalent force
[D] strong ionic force

Question #8
Which molecule is nonpolar?
[A] CO2
[B] H2O
[C] NH3
[D] HF

Question #9
Which of the following molecules is polar?
[A] CO2
[B] H2
[C] H2S
[D] SO2

Question #10
H2 is an asymmetrical molecule
True
False

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quiz 5

 

Question #1
How can the physical properties of substances be explained?
[A] In terms of chemical bonds only
[B] In terms of intermolecular forces only
[C] In terms of chemical bonds and intermolecular forces
[D] In terms of ionic bonding only

Question #2
In general, what do the physical properties of substances include?
[A] conductivity, malleability, solubility and hardness only
[B] conductivity, malleability, solubility, hardness, melting and boiling point only
[C] conductivity, solubility, hardness, melting and boiling point only
[D] solubility, hardness, melting and boiling point only

Question #3
What do ionic solids have between particles?
[A] very strong ionic bonds
[B] very weak ionic bonds
[C] relatively weak ionic bonds
[D] relatively strong ionic bonds

Question #4
What substances have intermolecular forces?
[A] metals
[B] ionic compounds
[C] molecules
[D] electrons

Question #5
Metallic bonds are formed when valence electrons are mobile.
True
False

Question #6
Which is a property of most nonmetallic solids?
[A] high electrical conductivity
[B] malleability
[C] brittleness
[D] high thermal conductivity

Question #7
Which statement describes a chemical property of iron?
[A] Iron conducts electricity and heat
[B] Iron can be drawn into a wire
[C] Iron can be flattened into sheets
[D] Iron combines with oxygen to form rust

Question #8
Which characteristic is a property of molecular substances?
[A] low boiling point
[B] high melting point
[C] good heat conductivity
[D] good electrical conductivity

Question #9
Which substance conducts electricity when melted but not when solid?
[A] a molecular compound
[B] an ionic compound
[C] a metal
[D] a nonmetal

Question #10
Which characteristic is a property of metallic substances?
[A] low boiling point
[B] no conductivity because there are no free moving electrons/ions
[C] not malleable because particles cannot slide pass one another
[D] relatively low solubility
 

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