Test 4
Consider the general valence electron configuration of ns2np5 and the following statements: (i) Elements with this electron configuration are expected to form -1 anions. (ii) Elements with this electron configuration are expected to have large positive electron affinities. (iii) Elements with this electron configuration are nonmetals (iv) Elements with this electron configuration form acidic oxides Which statements are true?
(i), (iii), and (iv)
(i) NO2- (ii) NO3- (iii) SO3^2- (iv) SO4^2- (v) BrO3- There can be four equivalent best resonance structures of ________.
(iv)
The oxidation number of iron in Fe2O3 is
+3
Hydrogen is unique among the elements because________.
1,2,3,5
Given that the average bond energies for C-H and C-Br bonds are 413 and 276 kJ/mol, respectively, the heat of atomization of bromoform (CHBr3) is _______ kJ/mol
1241
The diagram below is the Born-Huber cycle for the formation of crystalline potassium fluoride. Which energy change corresponds to the first ionization energy of potassium?
3
The diagram below is the Born-Huber cycle for the formation of crystalline potassium fluoride. Which energy change corresponds to the electron affinity of fluorine?
4
Which of the following correctly represents the second ionization of aluminum?
Al+ (g) → Al2+ (g) + e-
_________ have the lowest first ionization energies of the groups listed.
Alkali metals
The lewis structure of the CO3^2_ ion is ________.
Answer A
Of the choices below, which gives the order for first ionization energies?
Ar > Cl > S > Si> Al
Which atom can accommodate an octet of electrons, but doesn't necessarily have to accommodate an octet?
B
Based on the octet rule, boron will most likely form a ________ ion.
B3+
Which alkaline earth metal will not react with liquid water or with steam?
Be
A valid lewis structure of _____ cannot be drawn without violating the octet rule.
BeH2
Which of the following correctly represents the electron affinity of bromine?
Br (g) + e- → Br- (g)
In which set of elements would all members be expected to have very similar chemical properties?
Br,I ,At
Of the following species, _________ has the largest radius.
Br-
The central atom in_______ does not violate the octet rule.
CF4
A valid Lewis structure of ___ cannot be drawn without violating the octet rule.
CIF3
Of the following oxides, _______ is the most acidic.
CO2
Which one of the following compounds would produce an acidic solution when dissolved in water?
CO2
Which equation correctly represents the electron affinity of calcium?
Ca (g) + e- → Ca- (g)
Which equation correctly represents the first ionization of calcium?
Ca (g) → Ca+ (g) + e-
Which of the following does not have eight valence electrons?
Ca+
Of the following elements, _ has the most negative electron affinity.
Cl
Which of the following correctly represents the second ionization of copper?
Cu+ (g) → Cu2+ (g) + e-
Which of the following statements is not true for oxygen?
Dry air is about 79% oxygen.
In which of the molecules below is the carbon-carbon distance the shortest?
H-C≡C-H
Of the molecules below, the bond in _________ is the most polar.
HF
Which element is solid at a room temperature?
I2
A valid Lewis structure of __ cannot be drawn without violating the octet rule.
ICl5
A valid Lewis structure of _______ cannot be drawn without violating the octet rule.
IF3
Of the following, which gives the correct order for atomic radius for Ca, K, As, Ge and Kr?
K > Ca > Ge > As > Kr
The alkali metal that is used to treat main-depressive illness is __________.
Li
Of the following metals, ________ exhibits multiple oxidation states.
Ni
Which one of the following elements has an allotrope that is produced in the upper atmosphere by lightening?
O
Which of the following has the bonds correctly arranged in order of increasing polarity?
O-F, N-F, Be-F, Mg-F
Which of the following is an isoelectronic series?
O2-, F-, Ne, Na+
Which of the following correctly represents the electron affinity of phosphorus?
P (g) + e- → P- (g)
Which of the following correctly represents the second ionization of phosphorus?
P+ (g) → p2+ (g) + e-
Of the following elements,________ has the most negative electron affinity.
S
A valid Lewis structure of ____ cannot be drawn without violating the octet rule.
SeF4
The element in the periodic table that looks like a metal, is a poor thermal conductor, and acts as an electrical semiconductor is _________.
Si
The list that correctly indicates the order of metallic character is ________.
Si > P > S
Which of the following does not have eight valence electrons ?
Sr+
Why don't we draw double bonds between the Be atom and the Cl atoms in BeCl2?
That would give positive formal charges to the chlorine atoms and a negative formal charge to the beryllium atom.
Which one of the following is not true about the alkali metals?
They all have 2 electrons in their valence shells.
Of the possible bonds between carbon atoms (single, double, and triple),__________
a double bond is longer than a tripe bond
(i) NO2- (ii) NO3- (iii) SO3^2- (iv) SO4^2- (v) BrO3- In which of the ions do all X-O bonds (X indicates the central atom) have the same lenght?
all
Which of the following has eight valence electrons?
all of the above
Bond enthalpy is _______.
always positive
In the nitrate ion (NO2-),________.
both bonds are the same
Sodium is much more apt to exist as a cation than is chlorine. This is because _______.
chlorine has a greater ionization energy than sodium does
Transition metals within a period differ mainly in the number of ______ electrons.
d
As the number of covalent bonds between two atoms increases, the distance between the atoms_______ and the strength of the bond between them__________.
decreases, increases
Atomic radius generally increases as we move __________.
down a group and from right to left across a period
The Lewis structure of N2H2 shows________.
each nitrogen has one nonbonding electron pair
All of the halogens _______.
form salts with alkali metals with the formula MX
The alkali metal that is naturally radioactive is _________.
francium
Alkaline earth metals _________.
from basic oxides
Most explosives are compounds that decompose rapidly to produce__________ products and a great deal of ________.
gaseous, heat
Astatine has a(n)_______ density and a(n)__________ atomic radius compared to iodine.
greater; greater
In ionic bond formation, the lattice energy of ions ______ as the magnitude of the ion charges _______ and the radii _________.
increases, increase, decrease
The effective nuclear charge of an atom is primarily affected by ________.
inner electrons
In nature, sulfur is most commonly found in _________.
metal sulfides
In nature, the noble gases exist as ________.
monatomic gaseous atoms
Electrons in the 1s subshell are much closer to the nucleus in Ar than in He due to the larger______ in Ar.
nuclear charge
The type of compound that is most likely to contain a covalent bond is___________.
one that is composed of only nonmetals
The convert from one resonance structure to another, ___________.
only electrons can be moved
Resonance structures differ by ______.
placement of electrons only
The acidity of carbonated water is due to the _____.
reaction of CO2 and H2O
Consider the following properties of an element: (i) It is solid at room temperature. (ii)It easily forms an oxide when exposed to air. (iii)When it reacts with water, hydrogen gas evolves. (iv)It must be stored submerged in oil. Which element fits the above description the best?
sodium
Nonmetals can be ______ at room temperature.
solid, liquid, or gas
Lattice energy is ________.
the energy required to convert a mole of ionic solid into its constituent ions in the gas phase
Which of the following traits characterizes the alkali metals?
the lowest first ionization energies in a period
For resonance forms of a molecule or iron, _________.
the observed structure is an average of the resonance forms
The atomic radius of main-group elements generally increases down a group because_______.
the principle quantum number of the valence orbitals increases
Atomic radius generally decreases as we move ___________.
up a group and from left to right across a period
Of the bonds C-C, C=C, and C ≡, the C-C bond is__________.
weakest/longest
Of the bonds C-N, C=N, and C≡N, the C-N bond is _______.
weakest/longest
The noble gases were, until relatively recently, thought to be entirely unreactive. Experiments in the early 1960s showed that Xe could, in fact, form compounds with fluorine. The formation of compounds consisting of Xe is made possible by _________.
xenon's relatively low ionization energy
Of the following elements, which have been shown to form compounds? helium, neon, argon, krypton, xenon
xenon, krypton, and argon
Using the Born-Haber cycle, the ΔH˚f of KBr is equal to _________.
ΔH˚f [K (g)] + ΔH˚f [Br (g)] + I1(K) + E (Br) - ΔH lattice