Question 1

Which of the following is the second most abundant (by mass) element in the earth's crust, oceans, and atmosphere?
A) carbon
B) oxygen
C) silicon
D) hydrogen
E) aluminum

Accepted Answer

Silicon is the second most abundant element by mass in the Earth's crust, after oxygen. Oxygen is the most abundant element in both the Earth's crust and the oceans, but when considering the second place, silicon takes that position in the crust due to its prevalence in silicate minerals.

Question 2

Hydrogen is a nonmetal and lithium is an active metal, even though they are in the same group.
A) True. Such differences are common for elements in the same group.
B) False. Both hydrogen and lithium are nonmetals
C) True. This can be explained by the very large difference in atomic radii between hydrogen and lithium.
D) False. Because the elements are in the same group, they have similar metallic qualities.
E) none of these

Accepted Answer

C

Question 3

Choose the element with the smallest atomic radius.
A) Ra
B) Ca
C) Rb
D) K
E) Li

Accepted Answer

The atomic radius decreases as you move from left to right across a period and increases as you move down a group in the periodic table. Li is located in the top left corner of the periodic table, making it the element with the smallest atomic radius out of the options given.

Question 4

What is the most abundant (by mass) element found in the human body?
A) oxygen
B) carbon
C) calcium
D) hydrogen
E) water

Accepted Answer

Oxygen makes up about 65% of the human body's mass, primarily found in water and other organic compounds. Carbon and hydrogen are also abundant elements in the body, but not as much as oxygen. Calcium is an important element found in bones and teeth, but its mass contribution is not as significant as oxygen. Water is not an element, but a compound made up of hydrogen and oxygen atoms.

Question 5

Which of the following exhibits the greatest metallic character?
A) Li
B) Al
C) Rb
D) Be
E) Mg

Accepted Answer

Rb is located in the lower left corner of the periodic table, which is where metallic character is greatest. Additionally, Rb has the lowest ionization energy and the highest atomic radius out of the given choices, both of which are indicators of metallic character.

Question 6

Hydrogen and lithium react very differently, although they are both members of Group 1. What is the primary reason for this difference?
A) Metallic character increases going down a group.
B) Electron affinity increases going down a group.
C) There is a very large difference between the atomic radii of H and Li.
D) Ionization energy increases going down a group.
E) Electronegativity increases going down a group.

Accepted Answer

The primary reason for the different reactions between hydrogen and lithium is the very large difference between their atomic radii. Hydrogen has a radius of 53 pm, while lithium has a radius of 152 pm. This difference in size leads to significant differences in their physical and chemical properties.

Question 7

Choose the element with the smallest radius.
A) Al(s)
B) K(s)
C) Mg(s)
D) Li(s)
E) In(s)

Accepted Answer

The answer of Choose the element with the smallest radius.
A)...

Question 8

Which elements have chemical properties determined by the valence-level s and p electrons?
A) actinides
B) lanthanides
C) representative elements
D) transition metals
E) none of these

Accepted Answer

Representative elements are those in the s and p blocks of the periodic table, and their chemical properties are determined by the valence-level s and p electrons.

Question 9

Which group contains two elements that exhibit +2 and +4 oxidation states?
A) Group 7A
B) Group 5A
C) Group 1A
D) Group 4A
E) Group 3A

Accepted Answer

Group 4A elements (titanium, zirconium, and hafnium) exhibit +2 and +4 oxidation states.

Question 10

In which group are the elements listed in correct order of increasing first ionization energy? A) Al > Si > P B) Na > P > Cl C) Cs > Na > K D) K > Ca > Ge E) Cs < Rb < Na

Accepted Answer

The first ionization energy generally increases across a period and decreases down a group in the periodic table. Therefore, Cs < Rb < Na is the correct order of increasing first ionization energy.

Question 11

Within a group, as the atomic numbers of the elements increase, the
A) elements become less metallic.
B) atomic radii decrease.
C) ionization energies decrease.
D) atomic masses decrease.

Accepted Answer

As you move down a group in the periodic table, the atomic number increases, leading to an increase in atomic size and a decrease in ionization energy due to the increased distance of the outer electrons from the nucleus and increased electron shielding.

Question 12

What reason is given for the stability of C⎯C, N⎯N, and O⎯O bonds, compared to the instability of Si⎯Si, P⎯P, and S⎯S bonds?
A) Their metallic character varies greatly.
B) There are large differences in their abilities to form strong pi bonds.
C) There are large differences in their ionization energies.
D) There are large differences in their electronegativities.
E) none of these

Accepted Answer

The stability of a bond is related to its ability to form strong pi bonds, which are formed by overlapping of atomic orbitals. C⎯C, N⎯N, and O⎯O can form strong pi bonds due to their smaller atomic size and higher electronegativity. On the other hand, Si⎯Si, P⎯P, and S⎯S have larger atomic size and lower electronegativity, which results in weaker pi bond formation and less stability.

Question 13

Which group contains the most active metals?
A) Group 2A
B) Group 3A
C) Group 1A
D) Group 4A

Accepted Answer

Group 1A, also known as the alkali metals, contains the most active metals. These metals have a single valence electron, which they readily give up to form positive ions. They react vigorously with water and oxygen in the air, making them highly reactive. Group 2A also contains highly active metals, but they are not as reactive as those in Group 1A. Group 3A and 4A contain mostly non-metals and metalloids, respectively, and are not known for their reactivity.

Question 14

In a given period, this group has the element with the smallest ionization energy.
A) Group 3A
B) Group 7A
C) Group 8A
D) Group 2A
E) Group 1A

Accepted Answer

Group 1A (also known as the alkali metals) has the element with the smallest ionization energy because they have only one valence electron that is easily removed to form a positive ion. As you move across a period and from bottom to top of a group, ionization energy generally increases. Thus, elements in Group 3A, Group 7A, and Group 8A all have higher ionization energies than the alkali metals in Group 1A. Group 2A also has higher ionization energies than Group 1A because the elements in Group 2A have two valence electrons that are harder to remove than the single valence electron in Group 1A.

Question 15

Which of the following oxides is amphoteric?
A) BeO
B) MgO
C) BaO
D) SrO
E) CaO

Accepted Answer

BeO (Beryllium oxide) is amphoteric, meaning it can react with both acids and bases. This is due to the small size and high charge density of the Be2+ ion, which allows it to form covalent bonds with oxygen, leading to amphoteric behavior.

Question 16

The ion that aluminum is most likely to form is isoelectronic with
A) Si
B) Ne
C) Na
D) Cl
E) Mg

Accepted Answer

Aluminum, with an atomic number of 13, tends to lose three electrons to achieve a stable electron configuration, resulting in an Al^3+ ion. This ion has 10 electrons, the same as neon (Ne), which has an atomic number of 10, making them isoelectronic.

Question 17

Which of the following elements has the highest ionization energy?
A) Si
B) In
C) Tl
D) B
E) Ga

Accepted Answer

Boron (B) has the highest ionization energy among the given options because it is located furthest to the right and top of the periodic table, where ionization energy generally increases.

Question 18

In a given period, this group has the element with the smallest atomic radius.
A) Group 2A
B) Group 3A
C) Group 1A
D) Group 7A
E) Group 8A

Accepted Answer

The answer of In a given period, this group has...

Question 19

Choose the element that is the strongest reducing agent in aqueous solution.
A) K
B) Rb
C) Na
D) Cs
E) Li

Accepted Answer

Li is the strongest reducing agent among the given options because it has the lowest ionization energy and can easily lose an electron to form Li+ cation.

Question 20

Which of the following is a metalloid?
A) aluminum
B) carbon
C) fluorine
D) lithium
E) silicon

Accepted Answer

Silicon is a metalloid because it has properties that are intermediate between those of metals and nonmetals.

Quiz 18: The Representative Elements

Which of the following is the second most abundant (by mass) element in the earth's crust, oceans, and atmosphere?

Hydrogen is a nonmetal and lithium is an active metal, even though they are in the same group.

Choose the element with the smallest atomic radius.

What is the most abundant (by mass) element found in the human body?

Which of the following exhibits the greatest metallic character?

Hydrogen and lithium react very differently, although they are both members of Group 1. What is the primary reason for this difference?

Choose the element with the smallest radius.

Which elements have chemical properties determined by the valence-level s and p electrons?

Which group contains two elements that exhibit +2 and +4 oxidation states?

In which group are the elements listed in correct order of increasing first ionization energy?

Within a group, as the atomic numbers of the elements increase, the

What reason is given for the stability of C⎯C, N⎯N, and O⎯O bonds, compared to the instability of Si⎯Si, P⎯P, and S⎯S bonds?

Which group contains the most active metals?

In a given period, this group has the element with the smallest ionization energy.

Which of the following oxides is amphoteric?

The ion that aluminum is most likely to form is isoelectronic with

Which of the following elements has the highest ionization energy?

In a given period, this group has the element with the smallest atomic radius.

Choose the element that is the strongest reducing agent in aqueous solution.

Which of the following is a metalloid?