Mastering Chemistry Chapter 8 Modified

What is the formal charge of each of these atoms: HOFO

H-0
O-0
F-+1
O--1

Calculate the bond dissociation energy for the breaking of all the bonds in a mole of methane CH4?

1640 kJ/mol

What is the bond dissociation energy for the breaking of all the bonds in a mole of O2 molecules?

498 kJ/mol

Calculate the bond dissociation energy required for the breaking all the bonds in a mole of water molecules, H2O

920 kJ/mol

Calculate the bond dissociation energy required for the breaking all the bonds in a mole of carbon dioxide, CO2

1464 kJ/mol

Calculate the approximate enthalpy change, delta H*, for combustion of methane: CH4 + 2O2 --> 2H2O + CO2
CH4= 1640
O2=498
H2O=920
CO2=1464

-668 kJ

Which of these elements is most likely to form ions with 2+ ions?
Cl O Ca P Li

Ca

Which of these molecules has the same number of shared and unshared electron pairs?
HCl PF3 H2S Br2 CCl2F2

H2S

Which of the following bonds is the most polar?
Ga-Cl Se-F H-I H-F N-P

H-F

How many nonbonding electron pairs are there in the Lewis structure of the peroxide ion O2^-2?

6 because it contains 14 electrons, 6 nonbonding and 1 bonding

Which of these molecules has a Lewis structure with a central atom having no nonbonding electron pairs?

SiF4 and CO2

Place the following elements in order of decreasing atomic radius: Cl Pb Al F

Largest
Pb
Al
Cl
F
Smallest

Which element has the highest (most negative) electron affinity?
Ne S K Ca Cu

S

Classify each element as a metal, nonmetal, and semimetal: Ca, In, Xe, Zn, S, As

Metal= Ca, Zn, In
Nonmetal= Xe, S
Semimetal= As

Arrange the following elements in order of decreasing electronegativity:
Chlorine, Cesium, Chromium, Selenium

Most
Chlorine
Selenium
Chromium
Cesium
Least

An oxidant is a substance that can accept the electrons from another reagent. Use electronegativity values to determine which one of the following is a good oxidant:
O Li Ni

O

Use electronegativity values to determine which of the following you would expect to be the best insulator
Cl As Na

Cl
*more electronegativity= better insulator
**nonmetals best insulators but worst conductors

Classify the bonds formed between each pair as ionic, polar covalent, or nonpolar covalent quantitatively based solely on each element's position on the periodic table:
Ba&O S&F Br&Br P&P Cs&Cl Al&N O&F P&F

Ionic= Ba&O, Cs&Cl, Al&N
Polar Covalent= S&F, O&F, P&F
Nonpolar covalent= Br&Br, P&P

Element Sc Be H P S I Br Cl O F
Electronegativity 1.3 1.5 2.1 2.5 2.5 2.8 3 3.5 3.5 4
Classify the bonds based on the electronegativity table
Sc&O Be&F H&P H&Br Be&Cl S&I S&O

Ionic= Sc&O, Be&F (>2 difference)
Polar Covalent= H&Br, Be&Cl, S&O (<2 difference)
Nonpolar Covalent= H&P, S&I (equal electronegativity )

Which of the following has the highest boiling point?
F2, NaF, HF, ClF

NaF

Which of the following has 8 valence electrons?
Na^+, Kr, Cl^-, Ti^4+, all of the above

all of the above

True of False: Atoms surrounded by 8 valence electrons tend to lose electrons

False

Based on the octet rule, phosphorus most likely forms a _____ ion.
A) P³⁻
B) P⁺
C) P⁵⁻
D) P³⁺
E) P⁵⁺

A) P³⁻

Based on the octet rule, aluminum most like forms an ______ ion.
A) Al³⁻
B) Al⁺
C) Al⁵⁻
D) Al³⁺
E) Al⁵⁺

D) Al³⁺

The electron configuration of phosphide ion (P³⁻) is ___________

[Ne]3s^2 3p^6

The electron configuration of the sulfide ion (S^2-) is ________

[Ne]3s^2 3p^6

The only noble gas without 8 valence electrons is ______

Helium

Which of the following would have to lose 2 electrons to achieve a noble gas electron configuration?
O, Sr, Na, Se, Br

Sr

The _____ ion has a noble gas configuration

O^2-

Which species has the electron configuration: [Ar]2d^2
Mn^2+ K+ Fe^3+ Cr^2+ V^3+

V^3+

What is the electron configuration for the Co^2+ ion?

[Ar]3d^7

What is the electron configuration for the Fe^3+ ion?

[Ar]4s^0 3d^5

The ______ ion is represented by the electron configuration [Ar]3d^2

Fe^6+

The triple bond consists of ___ pairs of electrons shared between 2 atoms

3

The double bond consists of ___ pairs of electrons shared between 2 atoms

2

What is the max number of triple bonds that a carbon atom can form?

1

What is the max number of double bonds that a carbon atom can form?

2

By referring only to the periodic table, select the most electronegativity element in group 6A

O

By referring only to the periodic table, select the least electronegativity element: Al, Si, P

Al

By referring only to the periodic table, select the most electronegativity element: Ga, P, Cl, Na

Cl

By referring only to the periodic table, select element that is most likely to form an ionic compound with Ba: K, C, Zn, F

F

In the molecule below, which atom has the largest particle negative charge?
Cl
|
F --- C --- Br
|
I

F

Electronegativity __________ from left to right within a period and __________ from top to bottom within a group

increases, decreases

the ion ICl4- has _______ valence electrons

36

The Lewis structure of HCN (H bonded to C) shows that ____ has _____ nonbonding electron pair(s)

N, one

The formal charge on carbon in the molecule below is _______
. . . .
O = C = O
. . . .

zero

Which ionic bond is predicted to be stronger?
Mg-S or Na-Br

Mg-S