Chem Ch 8

True or false: Physical properties vary predictably across a given period in the periodic table.

False From left to right in the periodic table there is a large variation in physical properties from metals to metalloids to nonmetals. In contrast, down a group of elements with the same state, physical properties vary predictably.

Transition metals

Groups 3-12, 1-2 electrons in the outer energy level, less reactive than alsali-earth metals, shiny, good conductor of thermal energy and electrical current, high density behave similarly since they have a partially filled d subshell

Pb and Sn do not react with water but they do react with acid. Which of the following are products of the reaction of Sn with acid (H+)? Select all that apply.

H2 (g) Sn2+ (aq)

Which of the following are products of the reaction of N2O5 and P4O10 with water? Select all that apply.

H3PO4 HNO3

Match each alkali metal or group of alkali metals with the type of oxide each forms on reaction with O2. Instructions

Li oxides Na, K, Rb, Cs oxides and peroxides K, Rb, Cs oxides, peroxides, and superoxides

general trends observed in the formation of ions by main group elements?

Metals tend to lose electrons to form cations. Ions formed from main group elements have a noble-gas electron configuration.

The ________ element of any group in the periodic table tends to differ from the other members of the group.

first smallest

When forming an ion main group nonmetals will

gain electrons to fill the np sublevel

transition metals

have incomplete d subshells they readily produce cations with incompletely filled d subshells

For the representative elements, atomic radius ________ from top to bottom

increase

As we move down a group in the periodic table, both atomic and ionic radii tend to _____. Comparisons of ionic radii between groups can only be made if the species are isoelectronic. For an isoelectronic series of ions, cations are _____ than anions.

increase smaller

Electron affinity of metals are generally ______ than those of nonmetals

lower

Group 8A

noble gases

Which Group 6A element is MOST likely to form an anion with a charge of -2?

O S Se Te

Which monatomic ions have the electron configuration 1s22s22p6?

O2- F- Na+

Which Group 6A element is least likely to form an anion with a charge of -2?

Po

Which of the following species are isoelectronic with each other Se2- Zn2+ S2- K+ Ne

S2- K+

Which of the following options correctly describe the variation in oxide basicity in a given period of the periodic table? Select all that apply.

The oxides of elements in the middle of the period are most likely to be amphoteric. Oxides of elements at the left of the period tend to be basic.

Amphoteric

a substance that can act as both an acid and a base

ZnO P4O10 CaO

amphoteric acidic Basic

nuclear charge stays the same and electron - electron repulsion decreases

cation

The stability of noble gases has been attributed to their

complete valence ns and np subshells

The metallic character of the elements ________moving from left to right across the periodic table, causing the corresponding oxides to be _________acidic moving from left to right.

decrease more

As metallic character _____ from left to right across the periodic table, their oxides change from _____ to _____ to _____.

decreases; basic; amphoteric; acidic

When forming an ion metals in group 3A will

electrons lose np electrons first, then the ns electrons

Elements in Group 6A tend to _____ electron(s) when forming ions.

gain 2

Noble gases are also called the

inert gases

Halogens form _____ compounds with alkali metals and alkaline earth metals called metal halides. Halogens can also form _____ compounds with other halogens or nonmetals from other groups.

ionic; covalent

The energy (in units of kJ/mol) required to remove an electron from a gaseous atom is known as the ______

ionization

Designation of A and B groups

is not universal

Properties of Oxides Across a Period

left more basic right more acidic variability when its the first element of the group and is it is in the 1st and second period

When forming an ion transition metals will

lose ns electrons before losing (n - 1)d electrons

The alkali metals have _______ ionization energies compared to other elements in the same period, causing them all to be very reactive.

low

diatomic radius

one-half the distance between the centers of atoms in the molecules

Due to the very high ionization energies of noble gases, they will only react with extremely strong oxidizing agents. For this reason, the only two elements that have been observed to form bonds to the noble gases are _____ and _____.

oxygen fluorine

SO2 SO3

sulfur dioxide Sulfur trioxide

sulfur reacts with water to form

sulfuric acid

The alkaline earth metals generally have very low electron affinities because ______.

their ns subshells are completely filled

Halogen halides acidity trend

top to bottom weakest to strongest

Alkali metals react with ______ to form hydroxides, and react with ______ to form oxides, peroxides, and superoxides.

water ; oxygen

Noble gas

with the exception of Helium they have completely filled p subshells. n is the principal quantum number for the outermost shell

Group 8A: Noble Gases

-Least reactive (inert gases) -Stable electron configurations (all sublevels filled) -All elements want a configuration like that of a noble gas due to stability All Group 8A elements with n ≥ 2 have filled outer ns and np subshells. Group 8A elements have very low electron affinities.

as the ionization level increases, it will be greater than the previous level

2nd greater than 1st 3rd greater than 2nd

Which of the following statements correctly describe effective nuclear charge (Zeff)?

A lower Zeff makes a given electron easier to remove. The effective nuclear charge is lowered by electron-electron repulsions.

Transition element

An element in groups 3-12 on the periodic table no complete fills of d orbitals

Which oxide, BaO or MgO, is more basic? Why?

BaO The metal in this oxide is farther down the periodic table.

Which of the following options correctly describes the reactivity of alkaline earth metals with oxygen and acid? Select all that apply.

Ca, Sr, and Ba will undergo two different reactions in aqueous acid, not just one. Alkaline earth metals react with oxygen to produce metal oxides.

Match each element in Group 4A with its correct classification.

Carbon Nonmetal(s) Si and Ge Metalloid(s) Pb and Sn Metal(s)

Which of the following ions are isoelectronic with Ar

Cl- S2- K+

Group 7 A

Halogens are nonmetals with diatomic, never found in elemental form in nature Group 7A elements are all nonmetals. Anions derived from Group 7A elements have a -1 charge. gain 1 electron Group 7A is called the halogen group. Group 7A elements have large positive electron affinities.

As electrons are added to an atom, there is a(n) ______. in electron-electron repulsions. This causes an anion of a given element to be _______ than the neutral atom.

Increase larger

Which of the following properties are associated with alkali metals? Select all that apply.

Alkali metals readily form cations. Alkali metals are very reactive.

Which of the following options correctly describe the properties and reactivity of Group 3A elements? Select all that apply.

Aluminum reacts with acid to liberate hydrogen gas. Boron is a metalloid. Aluminum is a metal.

describe general trends in electron configurations?

Among main group elements the outer electron configurations within a group are identical. The period number of an element corresponds to the n value of the highest energy level containing electrons.

Which of the following statements correctly describe atomic radii of representative elements?

Atomic radii of main group elements decrease across a period. Atomic radii generally increase as n increases.

Which alkaline earth metal would be expected to differ the most from the others in its chemical and physical properties?

Beryllium Reason: Period 2 elements tend to differ from the other elements in their groups, mostly due to their significantly smaller size.

Which of the following species are isoelectronic with each other? Select all that apply. Cd 2+ Br- Sr2+ Mg2+ Ar

Br- Sr2+ They are both isoelectronic with Kr

valence electrons

Electrons on the outermost energy level of an atom

general trends observed in the chemical properties of the elements?

Elements in the same group tend to have similar chemical properties. The lightest element in each group often differs from the other members of the group. A group containing both metals and nonmetals will show a greater degree of variability than a group containing only one type of element.

Alkali metals

Group 1, 1 electron in outer level, very reactive, soft, silver, shiny, low density; Lithium, Sodium, Potassium, Rubidium, Cesium, Francium Electron config of ns1

diatomic molecules

H2, N2, O2, F2, Cl2, Br2, I2, At2

Although electron affinity generally increases from left to right across the periodic table, there are some exceptions. Which of the following pairs of elements do not follow this general trend? Select all that apply.

K vs. Ca Cl vs. Ar Si vs. P

f-block elements

Lanthanides and Actinides, wedged between GROUPS 3 AND 4 IN THE 5TH AND 6TH PERIODS Position of these inner transition elements reflects filling of the 4f sublevel

Lanthanides and actinides

Lanthanides- shiny reactive metals. Actinides radioactive, means they are unstable behave similarly because they have partially filled f subshells

Match the trends in metallic character and the description of each type of element correctly.

Metallic character decreases --- from left to right across a period Metallic character increases --- from top to bottom within a group Metals tend to have --- low ionization energies Nonmetals tend to have--- high electron affinities

2nd Ionization energy in order lowest to highest P Al Mg Si

Mg Si Al P Mg more readily loses its second electron because that electron is held by the lowest effective nuclear charge.

Which of the following properties are typical for alkaline earth metals? Select all that apply.

Most Be and some Mg compounds are molecular rather than ionic. Metallic character increases down the alkaline earth metal group. Alkaline earth metals tend to form +2 cations in ionic compounds.

Which statement correctly describes the reactivity of alkaline earth metals with water?

Most alkaline earth metals react with water to produce a metal hydroxide and hydrogen gas.

Between which two Group 5A elements would the difference in chemical and physical properties be greatest?

Nitrogen and bismuth Reason: The greatest difference is between the top and bottom of the group. Nitrogen is a nonmetal that exists as a diatomic gas; bismuth is a metal.

Which of the following are the most commonly found nitrogen- and phosphorous-containing compounds? Select all that apply.

Nitrogen forms many gaseous oxides. Most metallic nitrides (e.g., Li3N and Mg3N2) are ionic compounds. Phosphorous forms two solid oxides: P4O6 and P4O10.

electron affinity facts

Noble gases have negative values for electron affinity. elements in Group 5A have a lower electron affinity than elements in Group 4A. elements in Group 2A have a lower electron affinity than elements in Group 1A.

Using the modern periodic table, which element will have similar chemical properties to an element with Z = 7? Multiple choice question. O Cl P Rh

P

Which of the following options correctly describe the oxidation states of Group 4A elements? Select all that apply.

Pb tends to form compounds in which it has a +2 oxidation state. SnO2 is only slightly more stable than SnO.

For any element in the periodic table, the _______ number gives the n value of the highest principal energy level containing electrons. For main group elements only, the ___________ number is always equal to the number of valence electrons.

Period Group

In reference to Ionization energy. For a neutral element this energy is a measure of how easily the element forms an ion with a ___________ charge.

Positive

hIGHEST AFFINITY

THE HALOGENS GROUP 7a

Ionization energy

The amount of energy required to remove 1 mol of an electron from 1 mol of gaseous atoms or ions

core electrons

The electrons that are not in the outermost shell of an atom. Not valence

electron affinity

The energy change associated with the addition of an electron to an atom to form an anion is called the electron Electron affinity is the energy change that occurs when an electron is accepted by an atom in the gaseous state. Electron affinity values can be positive or negative. Electron affinity measures the tendency of an element to form an anion.

describe the numbering systems used for the periodic table

The nonsequential B numbering system is used to acknowledge the similarity in the number of outer electrons for transition and main group elements. The IUPAC has suggested using a system where the groups are numbered from 1-18.

original periodic table

The original periodic table was developed by Dmitri Mendeleev. The original periodic table had 66 elements. Some inconsistencies were present in the original periodic table. For example, Ar was listed as in the same group as the alkali metals. The original periodic table predicted the properties of elements that were not discovered until later.

Which of the following statements correctly describe the types of ions formed by Group 3A elements? Select all that apply.

The stability of cations with a +1 charge increases down Group 3A. All Group 3A elements except Al can form +1 and +3 ions.

Which of the following factors affect the type of oxide formed by an alkali metal? Select all that apply.

The stability of the oxide in the solid state The attraction between the metal cation (M+) and the oxygen anion present

Which of the following options correctly describe the shielding constant σ in the equation Zeff = Z - σ?

The value of σ cannot be greater than the value of Z. σ cannot be equal to zero in a many-electron system.

What does it mean if two species are isoelectronic?

They have the same number of electrons. They have the same electron configuration.

electron configurations for Se2-

[Kr] and the actual one found on the periodic table website

reason for the exception to the general trends for electron affinity (EA) to the appropriate group(s) of elements. EA lower for Group 2A than 1A matches

added electron in higher energy np orbital, well shielded from the nucleus

reason for the exception to the general trends for electron affinity (EA) to the appropriate group(s) of elements. EA lower for Group 5A than 4A

added electron placed in an already half-filled np orbital, increasing electron-electron repulsions

effective nuclear charge (Zeff) Zeff = Z - sigma

amount of charge felt by the most recently added electron when both the actual nuclear charge Z and the repulsive effects (shielding) of the other electrons are taken into account

Representative elements

an element in an "A" group in the periodic table; as a group these elements display a wide range of physical and chemical properties. In their atoms, the s and p sublevels in the highest occupied energy level are partially filled

Nuclear charge stays the same, electron-electron repulsion increases.

anion

IUPAC recommends numbering the columns sequentially with arabic numerals 1-18

arabic numerals 1-18

Modern Periodic table is arranged by

atomic number

If a group of the periodic table contains both metals and nonmetals, the metals will be found at the ______ of the group, while the nonmetals will be found at the ______.

bottom top

For the representative elements, atomic radius ________ from left to right across a period

decrease

In the alkaline earth metal group, the first and the second ionization energies _____ from Be to Ba. These metals therefore tend to form _____ ions; hence metallic character _____ down the alkaline earth metal group.

decrease; +2; increases

For a series of isoelectronic ions such as P3-, Cl-, K+, and Ca2+, ionic radius ______ as the atomic number increases.

decreases As atomic number increases in an isoelectronic series, the nuclear charge increases while the electron configuration remains the same. This will cause ionic radius to decrease.

The nuclear attraction that is felt by an electron in an atom is known as the ______ nuclear charge.

effective

The periodic table reflects the periodic recurrence of the properties of elements. This behavior reflects the _____ of the elements.

electron configurations

reason for the exception to the general trends for electron affinity (EA) to the appropriate group(s) of elements. Noble gases

electron is added to an (n + 1) orbital; very weakly attracted to the nucleus due to shielding by the core electrons

Ionization energy generally decreases down a group because as the outermost electron moves _____ the nucleus it takes _____ energy to remove it.

farther away from; less

Since fluorine is to the right of oxygen on the periodic table, its valence electrons experience a(n) _________ effective nuclear charge. Fluorine will have a(n) _______ ionization energy than oxygen.

greater Higher

For the main group elements of the periodic table, the _____ number indicates the number of ______.

group valence electrons

metallic radius

half the distance between the nuclei of two adjacent, identical metal atoms

Because of their common valence electron configuration, elements in the ______ group form ions with a charge of -1.

halogen

electron affinity trend

is and increase in the tendency to accept electrons (become more positive) from left to right across a period. The noble gases are the exception to this. varies little down a group

Mg2+, Na+, and F- all have the same electron configuration as Ne, and are described as being _____ with Ne and with each other.

isoelectronic

anions are ____ than their parent atoms

larger Nuclear charge stays the same, electron-electron repulsion increases.

Because valence electrons are ___________ effective than core electrons at shielding nuclear charge, the effective nuclear charge ____________moving from left to right across a period of the periodic table.

less increases

When forming an ion alkali and alkaline earth metals will

lose all electrons from ns sublevel

Alkali metals have _____ ionization energies, and therefore tend to form ions with a charge of _____.

low; +1 Reason: Alkali metals have low values for ionization energy; therefore, they tend to lose their one valence electron to form +1 ions.

alkaline earth metals

metallic elements in group 2 of the periodic table which are harder than the alkali metals and are also less reactive Electron config of ns2

Which of the following groups of elements have low values for electron affinity? Select all that apply.

noble gases Reason: Noble gases have a filled valence shell and do not tend to accept another electron. alkaline earth metals Reason: Metals tend to have low values for electron affinity. This explains why metals tend to form cations. alkali metals Reason: Metals tend to have low values for electron affinity. This explains why metals tend to form cations.

In europe Group B is for ________ and Group A is for _______ and it is the ___________ of the American convention

representative Transition metals Opposite

Group 1A - 7A

representative elements main group elements

isoelectronic

same electron config

cations are _____ than their parent atoms

smaller, the outermost electron is removed and repulsions between electrons are reduced

Changes from left to right

the increase in effective nuclear charge from left to right across a period and from the top to the bottom in a group for representative elements # of valence electrons increases and nuclear charge

Group 1B and 3B-8B

transition metals

Noble gases are reactive or un-reactive

unreactive since their valence shells are complete