Chapter 4 Test Review

Question 1

Explain the method that John Newland used to organize elements.

Answer 1

He arranged the known elements in order of increasing atomic mass and used the law of octaves.

Question 2

What method did Dmitri Mendeleev use to arrange his periodic table?

Answer 2

He created the first periodic table by atomic mass and properties using Newland’s observations.

Question 3

Why did Mendeleev have gaps in his table? How did he use these gaps?

Answer 3

Mendeleev left gaps in the table for elements that have not yet been discovered and was able to predict these unknown elements properties.

Question 4

What was Henry Moseley’s contribution to the periodic table?

Answer 4

Provided the base to organize the elements on the table

Question 5

Explain the importance of valence electrons.

Answer 5

Valence electrons determine the atom’s chemical properties and are the electrons in the outermost shell of the atom.

Question 6

Why do elements with similar properties appear at regular intervals in the periodic table?

Answer 6

It shows periodic law which means elements are sorted by atomic number which lets elements with similar properties appear at regular intervals.

Question 7

How is the electron configuration similar for each element in a group?

Answer 7

The ending sublevel is always the same as the group it is.

Question 8

How is the electron configuration similar for each element in a period?

Answer 8

The same number of energy levels are filled.

Question 9

The ___ have a single electron in the highest occupied energy level.

Answer 9

Alkali metals

Question 10

The ____ are in the s- and p-blocks of the periodic table.

Answer 10

main-group elements

Question 11

All the _____ have two valence electrons and get to a stable e- configuration by losing two electrons.

Answer 11

Alkaline earth metals

Question 12

Unlike the main group elements, each group of the _____ does not have the identical outer electron configuration.

Answer 12

transition metals

Question 13

The ____, the most reactive group of nonmetals, achieve stable electron configurations by gaining one electron.

Answer 13

halogens

Question 14

The ___ have a full set of electrons in their outermost energy level.

Answer 14

noble gases

Question 15

The ___ are highly reactive and readily form salts with metals.

Answer 15

halogens

Question 16

The ____ are very stable and have low reactivity

Answer 16

noble gases

Question 17

In general, the _____ are metals that are less reactive than the alkali metals and the alkali earth metals.

Answer 17

transition metals

Question 18

The____ are metals that lose one electron when they react with water to form alkaline solutions.

Answer 18

alkali metals

Question 19

Most elements are ____

Answer 19

metals

Question 20

With its one valence electron, _____ reacts with many other elements.

Answer 20

hydrogen

Question 21

Which groups compose the main-group elements?

Answer 21

1,2, 13-18

Question 22

Why are the main-group elements called the representative elements?

Answer 22

They have a wide range of properties

Question 23

Why are Group 2 elements less reactive than Group 1 elements?

Answer 23

Group 2 have 2 valence electrons and would have to lose both to become stable.

Question 24

Using electron configurations, explain why the halogens readily react with the alkali metals to form salts.

Answer 24

Halogens need to gain one electron and alkali metals will lose the electron.

Question 25

Why is an iron alloy, such as steel, preferred over pure iron?

Answer 25

They tend to be harder, stronger, and more resistant to corrosion

Question 26

In the transition elements, electrons are usually added to the __ orbital, which is why these elements are also known as the _________

Answer 26

d, d-block elements

Question 27

The ___ include all members of Groups 1 through 12, as well as some of the elements of Groups ___ through _____.

Answer 27

metals, 13, 16

Question 28

The ___ include all of the elements in Group 17 and 18 as well as some members of Groups __ through ____.

Answer 28

non-metals, 14,16

Question 29

In the _____, electrons are being added to the 4f orbitals.

Answer 29

lanthanides

Question 30

In the _____, electrons are being added to the 5f orbitals. The ____ are unique in all that are unstable and radioactive.

Answer 30

actinides

Question 31

The amount of energy needed to remove an electron from a specific atom is called the ___ energy of an atom.

Answer 31

ionization

Question 32

____ is the energy change that occurs when a neutral atom gains an electron

Answer 32

Electron affinity

Question 33

The ____ is half the distance from center to center of two atoms bonded together.

Answer 33

bond radius

Question 34

_____ is a numerical value that reflects how much an atom in a molecule attracts electrons.

Answer 34

electronegativity

Question 35

As the nuclear charge increases across a period, the effective nuclear charge ______________ pulling the electrons closer to the nucleus and ____________ the size of the atom.

Answer 35

increases, decreases

Question 36

Explain why the exact size of an atom is difficult to determine.

Answer 36

An atom’s size depends on electrons that move, so the electron cloud has a “fuzzy” boundary.

Question 37

What is electron shielding?

Answer 37

Inner electrons shield outer electrons from the nucleus

Question 38

Explain why ionization energies tend to decrease down a group.

Answer 38

the outermost electron is farther from the nucleus, meaning it is held less tightly and requires less energy to remove

Question 39

Explain the large decrease in atomic radii as you move across a period from group 1 to group 14:

Answer 39

As the outermost electrons are pulled closer to the nucleus, they also get closer to one another and repulsion gets stronger.

Question 40

Explain the large increase in electronegativity as you move across a period:

Answer 40

each atom has one more proton and one more electron in the same principal energy level than the one before it. Therefore because electron shielding does not change, the nuclear charge increases across a period, attracting the electrons more strongly.

Question 41

Describe the periodic trend of ionization energy.

Answer 41

Decreases down a group, increases across a period from left to right

Question 42

Describe the periodic trend of atomic radius.

Answer 42

Increases down a group, decreases moving across a period from left to right

Question 43

Describe the periodic trend of ionic size.

Answer 43

Increases down a group, decreases across a period from left to right

Question 44

Describe the periodic trend in electron affinity.

Answer 44

Decreases down a group, increases across a period from left to right

Question 45

Describe the periodic trend of electronegativity.

Answer 45

Decreases down a group, increases across a period from left to right

Question 46

What is the octet rule?

Answer 46

the tendency of atoms to prefer to have eight electrons in the valence shell

Question 47

Atomic radii cannot be measured directly because the electron cloud surrounding the nucleus does not have a clearly defined____

Answer 47

mass

Question 48

The general trend in the radius of an atom moving down a group is partially accounted for by the ____

Answer 48

shielding of the outer electrons by the inner electrons

Question 49

What is the periodic table?

Answer 49

A table that organizes elements by their properties

Question 50

Elements on our periodic table are in order of increasing

Answer 50

both atomic number and number of protons

Question 51

Elements with similar electron configurations ____

Answer 51

have similar reactivities

Question 52

Metalloids are ____

Answer 52

semi-conductors

Question 53

Electron Affinity is ____

Answer 53

the amount of energy required to add an electron to an atom

Question 54

Electronegativity is ____

Answer 54

the measure of the tendency an atom to attract electrons