chemistry periodic table test

cation

A positive ion

Group 17 elements, the halogens, are the most reactive of the nonmetal elements because they A. require only one electron to fill their outer  energy level. B. have the highest ionization energies. C. have the largest atomic radii. D. are the farthest to the right in the periodic table.

A. require only one electron to fill their outer  energy level.

Which of the following elements has the highest electronegativity? A. oxygen. B. hydrogen. C. fluorine. D. carbon.

C. fluorine.

periods

Elements are also organized horizontally in rows

GROUP CONFIGURATIONS -GROUP 3 - GROUP 4 -GROUP 5 -GROUP 6 -GROUP 7 -GROUP 8 -GROUP 9 -GROUP 10 --GROUP 11 -GROUP 12

(n-‐1)d^1-‐10ns^0-‐2

Cannizzaro

was the first chemist to present a method for accurately measuring the relative masses of atoms.

GROUP CONFIGURATIONS -GROUP1 -GROUP2

-ns1 -ns2

. Which list ranks the elements Sr, Te, Kr, Ru, and Cs in order of increasing electron affinity? A. Sr < Te < Ru < Cs < Kr B. Te < Ru < Sr < Cs < Kr C. Cs < Sr < Ru < Te < Kr D. Kr < Cs < Sr < Ru < Te

D. Kr < Cs < Sr < Ru < Te

Name the block and group in which each of the following elements is located in the periodic table. Then, use the periodic table to name each element. Identify each element as a metal, nonmetal, or metalloid. Finally, describe whether each element has high reactivity or low reactivity. a. [Xe]4f145d96s1 c. [Ne]3s23p6 b. [Ne]3s23p5 d. [Xe]4f66s2

The 4f sublevel is filled with 14 electrons. The 5d sublevel is partially filled with nine electrons. Therefore, this element is in the d block. The element is the transition metal platinum, Pt, which is in Group 10 and has a low reactivity. The incompletely filled p sublevel shows that this element is in the p block. A total of seven electrons are in the ns and np sublevels, so this element is in Group 17, the halogens. The element is chlorine, Cl, and is highly reactive. . This element has a noble-gas configuration and thus is in Group 18 in the p block. The element is argon, Ar, which is an unreactive nonmetal and a noble gas. The incomplete 4f sublevel shows that the element is in the f block and is a lanthanide. Group numbers are not assigned to the f block. The element is samarium, Sm. All of the lanthanides are reactive metals.

The periodic law states that A. the chemical properties of elements can be grouped according to periodicity. B. the properties of the elements are functions of atomic mass. C. all elements in the same group have the same number of valence electrons. D. all elements with the same number of occupied energy levels must be in the same group.

the chemical properties of elements can be grouped according to periodicity.

Valence electrons

the electrons available to be lost, gained, or shared in the formation of chemical compounds

Group ..... gains electrons easily.

17

As you move left to right across Period 3 from Mg to Cl, the energy needed to remove an electron from an atom A. generally increases. B. generally decreases. C. does not change. D. varies unpredictably.

A. generally increases.

Of the elements magnesium, Mg, chlorine, Cl, sodium, Na, and phosphorus, P, which has the largest atomic radius? Explain your answer in terms of trends of the periodic table.

All of the elements are in the third period. Of the four, sodium has the lowest atomic number and is the first element in the period. Atomic radii decrease across a period.

Of the elements gallium, Ga, bromine, Br, and calcium, Ca, which has the highest electronegativity? Explain your answer in terms of periodic trends.

All of these elements are in the fourth period. Bromine has the highest atomic number and is farthest to the right in the period. Bromine should have the highest electronegativity because electronegativity increases across the periods.

. The second ionization energies for the elements S-Ti are listed in a scrambled order below. Assign the correct IE2 value to each element (Hint: S has IE2 = 2251 kJ/mol, and Ti has IE2 = 1310 kJ/mol.) Explain your reasoning. IE2 values (kJ/mol): 2666, 2297, 3051, 1235, 2251, 1310, and 1145

Answer: S: 2551 kJ/mol; Cl: 2297 kJ/mol; Ar: 2666 kJ/mol; K: 3051 kJ/mol; Ca: 1145 kJ/mol; Sc: 1235 kJ/mol; Ti: 1310 kJ/mol. For the second ionization, the general trend is for increasing IE2 across the period in Groups 218 with Group 1 having the highest IE2. IE2 decreases going down a group.

. Which two elements are more likely to have the same charge on their ions? A. Se and As B. Sn and Si C. Ca and Rb D. I and Xe

B. Sn and Si

In the modern periodic table, elements are arranged according to A. decreasing atomic mass. B. Mendeleev's original model. C. increasing atomic number. D. when they were discovered.

C. increasing atomic number.

Which electron configuration is not correct? A. O2- [He]2s22p6 B. Mg2+ [He]2s22p6 C. V3+ [Ar]4s2 D. Al3+ [Ar]2s22p6

D. Al3+ [Ar]2s22p6

Ion Formation and Ionic Radii

Electrons in the highest occupied sublevel are always removed first.

Consider two main-group elements, A and B. Element A has a first ionization energy of 419 kJ/mol. Element B has a first ionization energy of 1000 kJ/mol. Decide if each element is more likely to be in the s block or p block. Which element is more likely to form a positive ion?

Element A has a very low ionization energy, which means that atoms of A lose electrons easily. Element A is most likely to be an s-block metal because ionization energies increase across the periods. Element B has a very high ionization energy which means that atoms of B have difficulty losing electrons. Element B would most likely lie at the end of a period in the p block. Element A is more likely to form a positive ion because it has a much lower ionization energy than element B does.

An element has the electron configuration [Kr]4d55s1. Without looking at the periodic table, identify the period, block, and group in which this element is located. Then, consult the periodic table to identify this element and the others in its group.

For d-block elements, the number of electrons in the ns sublevel (1) plus the number of electrons in the (n  1)d sublevel (5) equals the group number, 6. There are five electrons in the d sublevel, which means that it is incompletely filled. The d sublevel can hold 10 electrons. Therefore, the element is in the d block.

Ionization Energy

Generally increase across the period and increase down each group

. What group most commonly forms 2- ions? Explain your reasoning.

Group 16 most commonly forms 2- ions, because these elements require only two more electrons to fill their shell (obtain a noble-gas configuration).

The s-‐block elements:

Groups 1 & 2; group # = # electrons in ns sublevel

The p-‐block elements:

Groups 13-‐18:group # = # of electrons in ns & np sublevels + 10

The d-‐block elements:

Groups 3-‐12: although newly added electrons occupy the d-‐sublevels, the first electrons to be removed are those in the outermost sublevels.

In general, nonmetals have higher .....

IE than metals do.

Without looking at the periodic table, write the electron configuration for the Group 1 element in the third period. Is this element likely to be more reactive or less reactive than the element described in (a)?

In a third-period element, the highest occupied energy level is the third main energy level, n = 3. The 1s, 2s, and 2p sublevels are completely filled. This element has the following configuration: 1s22s22p63s1 or [Ne]3s1 Because it is in Group 1, this element is likely to be more reactive than the element described in (a), which is in Group 2.

valence electrons.

The electrons available to be lost, gained, or shared in the formation of chemical compounds

. Without looking at the periodic table, identify the group, period, and block in which the element that has the electron configuration [Xe]6s2 is located.

The element is in Group 2, as indicated by the group configuration of ns2. It is in the sixth period, as indicated by the highest principal quantum number in its configuration, 6. The element is in the s block

Without looking at the periodic table, write the outer electron configuration for the Group 14 element in the second period. Then, name the element, and identify it as a metal, nonmetal, or metalloid.

The group number is higher than 12, so the element is in the p block. The total number of electrons in the highest occupied s and p sublevels is therefore equal to the group number minus 10 (14  10 = 4). Two electrons are in the s sublevel, so two electrons must also be present in the 2p sublevel. The outer electron configuration is 2s22p2. The element is carbon, C, which is a nonmetal.

The lower the IE, ........

The lower the IE, the more easily electrons are lost, resulting in high reactivity.

possess a complete valence shell and do not usually attract electrons.

The noble gases

anion.

a negetaive ion

A jump in ionization energy occurs when an ion assumes ......

a noble-gas configuration

The second row of the f block, the ...., are between actinium and rutherfordium. The actinides are all radioactive.

actinides

In their pure state, all of the alkali metals have a silvery appearance and are soft enough to cut with a knife.

alkali metals

The elements of Group 1 of the periodic table are known as the .......

alkali metals

The elements of Group 2 of the periodic table are called the .....

alkaline-earth metals.

metals are less reactive than the alkali metals, but are still too reactive to be found in nature in pure form.

alkaline-earth metals.

Each successive electron removed from an ion feels ,,,,,,,,,.

an increasingly stronger effective nuclear charge.

Metals at the left form ....... and nonmetals at the upper left form ......

cations anions

Valence electrons hold atoms together in ...........

chemical compounds.

Mendeleev

created a table in which elements with similar properties were grouped together—a periodic table of the elements. (He arranged the elements by increasing atomic mass)

Cationic and anionic radii........across a period

decrease

Among the main-group elements, ionization energies generally.....

decrease down the groups.

Electron affinity generally ......... down groups

decreases

Atomic radius ......... from left to right within a period.

decreases (This is caused by the increase in the number of protons and electrons across a period.)

Moseley

discovered that the elements fit into patterns better when they were arranged according to atomic number, rather than atomic weight.

The energy change that occurs when an electron is acquired by a neutral atom is called the atom's......

electron affinity.

the most electronegative element is...

fluorine

Atomic Radii

generally decrease across the period

The ....... are the most reactive nonmetals.

halogens

noble gases

have completely filled valence shells. Because they are extremely stable, they are relatively unreactive. They have very high IE's and low electronegativity because they have no desire to gain or lose an electron.

. The noble gases have A. high ionization energies. B. high electron affinities. C. large atomic radii. D. a tendency to form both cations and anions.

high ionization energies.

Electron affinity generally .......across periods

increases

Atomic radius ......... from top to bottom within a group. (This is caused by electron shielding.)

increases (this is caused by electron shielding)

Increasing nuclear charge is responsible for both .....

increasing ionization energy and decreasing radii across the periods

An ..... is an atom or group of bonded atoms that has a positive or negative charge

ion

Any process that results in the formation of an ion is referred to as ....

ionization

The energy required to remove one electron from a neutral atom of an element is the ....

ionization energy,

The energy required to remove one electron from a neutral atom of an element is the........

ionization energy, IE

Electronegativity

is a measure of the ability of an atom in a chemical compound to attract electrons from another atom in the compound.

The Periodic Table

is an arrangement of the elements in order of their atomic numbers so that elements with similar properties fall in the same column, or group.

The first row of the f block, the ....., are shiny metals similar in reactivity to the Group 2 alkaline metals.

lanthanides

Atoms tend to be ...... the farther down in a group they are found.

larger

Chemical compounds form because electrons are .........between atoms.

lost, gained, or shared

The p-block elements together with the s-block elements are called the....

main-group elements.

Atomic radius

may be defined as one-half the distance between the nuclei of identical atoms that are bonded together.

all six ..... are also in the p block

metalloids

As atomic # increases, .......

more electrons lie between the nucleus and the electrons in the highest level, shielding the outer electrons from the nuclear charge.

At its right-hand end, the p block includes all of the .....

nonmetals

GROUP CONFIGURATIONS -GROUP 13 -GROUP 14 -GROUP 15 - GROUP 16 - GROUP 17 -GROUP 18

ns^2np^1-‐6

As atomic # increases, both the period and the group trends become less.....

pronounced

Atoms tend to be ..... the farther to the right they are found across a period

smaller

The Periodic Law

states that the physical and chemical properties of the elements are periodic functions of their atomic numbers.

The periodic table is divided into four blocks

the s, p, d, and f blocks.

The d-block elements are metals with typical metallic properties and are often referred to as.....

transition elements.