Question 1

What is the formula of the compound formed when potassium dichromate is dissolved in aqueous base? A)K₂CrO₄ B)K₂Cr₂O₇ C)CrO₃ D)Cr(OH)₃

Accepted Answer

A

Question 2

Except for scandium and titanium,all the 3d transition metals form divalent ions in aqueous solution.

Accepted Answer

True

Question 3

In the d-block elements,the third-row metallic radii are about the same as the second-row radii because of
A)the lanthanide contraction.
B)the third-row metallic radii are greater than the second-row radii.
C)the increased number of d-electrons.
D)greater shielding of f-electrons.
E)greater shielding of d-electrons.

Accepted Answer

The lanthanide contraction is a phenomenon in which the atomic radii of the elements in the lanthanide series are smaller than predicted due to the increased nuclear charge being partially offset by poor shielding of the 4f electrons. This contraction affects the properties of the d-block elements that follow, resulting in their third-row metallic radii being similar to the second-row radii.

Question 4

For the oxides CrO,Cr₂O₃,and CrO₃,which of the following is true? A)All the oxides are basic. B)All the oxides are acidic. C)CrO is acidic,and Cr₂O₃ and CrO₃ are basic. D)CrO and Cr₂O₃ are acidic and CrO₃ is basic. E)CrO is basic,Cr₂O₃ is amphoteric,and CrO₃ is acidic.

Accepted Answer

CrO is a basic oxide. 
CrSb12O13 and CrO2Sb13 are amphoteric oxides that can act as both acidic and basic oxides. 
CrO3 is an acidic oxide. Therefore, option E is the correct choice.

Question 5

The properties of the transition metals vary greatly but they all have
A)high densities and high melting points.
B)the same physical properties.
C)oxides that are used to produce alloys.
D)low boiling points.
E)the same strength as their alloys.

Accepted Answer

Transition metals are known for their high densities and high melting points, which is a common characteristic regardless of their individual properties.

Question 6

Which of the following pairs have about the same atomic radius?
A)Cu and Ag
B)Co and Rh
C)Fe and Ru
D)Mn and Tc
E)Ru and Os

Accepted Answer

The answer of Which of the following pairs have about...

Question 7

The atomic radii of the Period 6 d-metals are
A)smaller than expected,and about the same as the Period 5 d-metals.
B)about the same as the lanthanides.
C)larger than the atomic radii of the Period 5 d-metals.
D)about the same as the Period 4 d-metals.
E)large because of the lanthanide contraction.

Accepted Answer

The atomic radii of Period 6 d-metals are smaller than expected and are about the same as the Period 5 d-metals due to the lanthanide contraction. The lanthanide contraction is the phenomenon where the 4f electrons do not shield the outer electrons effectively, leading to a greater effective nuclear charge on the outer electrons and thus smaller atomic radii. This effect is seen when comparing the atomic radii of Period 5 and Period 6 d-metals, where they are unexpectedly similar.

Question 8

The d-metals can be mixed together to form a wide range of alloys because
A)the d-electrons interact strongly with each other.
B)the d-metals have a wide range of metal radii.
C)the nucleus is well shielded by the d-electrons.
D)the range of d-metal radii is not very great.
E)the d-metals have low melting points.

Accepted Answer

The answer of The d-metals can be mixed together to...

Question 9

Which of the following oxides is likely to be acidic? A)Mn₂O₇ B)MnO₂ C)Mn₂O₇ and MnO D)Mn₂O₃ E)MnO

Accepted Answer

The answer of Which of the following oxides is likely...

Question 10

Which of the following is likely to be a good reducing agent? A)Cr₂O₇^2- B)MnO₄^- C)Cr²⁺ D)MnO₂ E)Cr₂O₃

Accepted Answer

The answer of Which of the following is likely to...

Question 11

Vanadium metal is produced by the A)reduction of VOCl₂(s)with magnesium. B)reduction of vanadium(V)oxide with calcium. C)reaction of V₂O₅(s)with coke. D)decomposition of VCl₄(g)at high temperature. E)roasting of VO₂(s).

Accepted Answer

The answer of Vanadium metal is produced by the
A)reduction of...

Question 12

Which of the following would be the strongest acid in aqueous solution? A)Mg(OH₂)₆²⁺(aq) B)V(OH₂)₆²⁺(aq) C)Ni(OH₂)₆²⁺(aq) D)Sc(OH₂)₆³⁺(aq) E)Fe(OH₂)₆²⁺(aq)

Accepted Answer

The acidity of the metal hydroxides depends on the ability of the metal ion to polarize and stabilize the negative charge on the hydroxide ion. The higher the charge on the metal ion, the more polarizing power it has and the stronger the acid it forms. Scandium (Sc) has a +3 charge, which is higher than Mg, V, Ni, and Fe, giving it the highest polarizing power and making its hydroxide, Sc(OH)3, the strongest acid among the given options.

Question 13

Which of the following is expected to be the best oxidizing agent? A)Cu⁺(aq) B)Ti³⁺(aq) C)CrO₄^2-(aq) D)VO₂⁺ E)Cr²⁺(aq)

Accepted Answer

The best oxidizing agent is the species that can accept electrons easily or donate oxygen readily. The species with the highest oxidation state is the best oxidizing agent. Among the given options, the species in choice C, which contains Cr with an oxidation state of +6, is expected to be the best oxidizing agent as it has the highest oxidation state. The other options have lesser oxidation states of the central metal atom/ion.

Question 14

The maximum oxidation states for chromium and manganese are
A)both +7.
B)+7 and +8,respectively.
C)+3 and +4,respectively.
D)+5 and +6,respectively.
E)+6 and +7,respectively.

Accepted Answer

The maximum oxidation state for chromium is +6, and the maximum oxidation state for manganese is +7.

Question 15

Of the following,which possesses the smallest atomic radius?
A)Cd
B)Zn
C)Mo
D)Pd
E)Ru

Accepted Answer

Zn (Zinc) has the smallest atomic radius among the options given. Atomic radius generally decreases across a period from left to right in the periodic table due to the increase in nuclear charge, which pulls the electrons closer to the nucleus. Zn is located to the right of all the other elements listed (Cd, Mo, Pd, Ru) in the periodic table, making it have the smallest atomic radius among the options.

Question 16

The metalloproteins hemoglobin and vitamin B₁₂ contain the metals A)iron and zinc,respectively. B)cobalt and nickel,respectively. C)iron and Mo,respectively. D)manganese and iron,respectively. E)iron and cobalt,respectively.

Accepted Answer

Hemoglobin contains iron, which is essential for oxygen transport in the blood. Vitamin B12 contains cobalt, which is a key component of its structure.

Question 17

Most d-block elements have only one common oxidation state.

Accepted Answer

Most d-block elements have multiple common oxidation states.

Question 18

Which of the following is likely to be a good oxidizing agent? A)Fe²⁺ B)Cr²⁺ C)V²⁺ D)Mn²⁺ E)MnO₄^-

Accepted Answer

The answer of Which of the following is likely to...

Question 19

For a given metal,the oxides become more basic with increasing oxidation state.

Accepted Answer

In general, for a given metal, the oxides become more acidic with increasing oxidation state, as higher oxidation states tend to attract more oxygen, leading to more covalent character and acidic behavior.

Question 20

The lanthanide contraction results because
A)the shielding effect of the d-electrons is less than that of the f-electrons.
B)the shielding effect of the d-electrons is greater than that of the f-electrons.
C)of the poor shielding effect of the f-electrons and the higher nuclear charge.
D)the d-electrons shield the f-electrons from the nucleus.
E)f-electrons interact more strongly with each other than d-electrons.

Accepted Answer

The lanthanide contraction occurs because the f-electrons have poor shielding capabilities, which leads to the higher nuclear charge being more effective in pulling the outer electrons closer to the nucleus. This results in a smaller ionic radius and a higher effective nuclear charge for the elements in the lanthanide series.

Quiz 17: The Elements: The D Block

What is the formula of the compound formed when potassium dichromate is dissolved in aqueous base?

Except for scandium and titanium,all the 3d transition metals form divalent ions in aqueous solution.

In the d-block elements,the third-row metallic radii are about the same as the second-row radii because of

For the oxides CrO,Cr2O3,and CrO3,which of the following is true?

The properties of the transition metals vary greatly but they all have

Which of the following pairs have about the same atomic radius?

The atomic radii of the Period 6 d-metals are

The d-metals can be mixed together to form a wide range of alloys because

Which of the following oxides is likely to be acidic?

Which of the following is likely to be a good reducing agent?

Vanadium metal is produced by the

Which of the following would be the strongest acid in aqueous solution?

Which of the following is expected to be the best oxidizing agent?

The maximum oxidation states for chromium and manganese are

Of the following,which possesses the smallest atomic radius?

The metalloproteins hemoglobin and vitamin B12 contain the metals

Most d-block elements have only one common oxidation state.

Which of the following is likely to be a good oxidizing agent?

For a given metal,the oxides become more basic with increasing oxidation state.

The lanthanide contraction results because

For the oxides CrO,Cr₂O₃,and CrO₃,which of the following is true?

The metalloproteins hemoglobin and vitamin B₁₂ contain the metals