English
Karnataka Board PUCPUC Science 2nd PUC Class 12

Although Zirconium belongs to 4d transition series and Hafnium to 5d transition series even then they show similar physical and chemical properties because ______.

Advertisements
Advertisements

Question

Although Zirconium belongs to 4d transition series and Hafnium to 5d transition series even then they show similar physical and chemical properties because ______.

Options

  • both belong to d-block.

  • both have same number of electrons.

  • both have similar atomic radius.

  • both belong to the same group of the periodic table.

MCQ
Fill in the Blanks
Advertisements

Solution

Although Zirconium belongs to 4d transition series and Hafnium to 5d transition series even then they show similar physical and chemical properties because both have similar atomic radius.

Explanation:

Zirconium and hafnium have similar atomic radius hence they show similar physical and chemical properties.

shaalaa.com
  Is there an error in this question or solution?
Chapter 8: The d-and f-Block Elements - Multiple Choice Questions (Type - I) [Page 109]

APPEARS IN

NCERT Exemplar Chemistry Exemplar [English] Class 12
Chapter 8 The d-and f-Block Elements
Multiple Choice Questions (Type - I) | Q 20 | Page 109

RELATED QUESTIONS

Which metal in the first transition series (3d series) exhibits + 1 oxidation state most frequently and why?


`E_((M^(2+)/M)`

Cr Mn Fe Co Ni Cu
-0.91 -1.18 -0.44 -0.28 -0.25 -0.34

From the given data of E0 values, answer the following questions :

(1) Why is `E_(((Cu^(2+))/(Cu)))` value exceptionally positive

(2) Why is `E_(((Mn^(2+))/(Mn)))` value is highly negative as compared to other elements

(3) Which is the stronger reducing agents Cr2+ or Fe2+ ? Give Reason.


Out of Mn3+ and Cr3+, which is more paramagnetic and why ?

(Atomic nos. : Mn = 25, Cr = 24)


Comment on the statement that elements of the first transition series possess many properties different from those of heavier transition elements.


Complete and balance the following chemical equations

`MnO_4^(-) + H_2O + I^(-) ->`


Give reasons: Sc3+ is colourless in aqueous solution whereas Ti3+ is coloured.


Which among the following transition metal has the lowest melting point?


Read the passage given below and answer the following question:

The transition metals when exposed to oxygen at low and intermediate temperatures form thin, protective oxide films of up to some thousands of Angstroms in thickness. Transition metal oxides lie between the extremes of ionic and covalent binary compounds formed by elements from the left or right side of the periodic table. They range from metallic to semiconducting and deviate by both large and small degrees from stoichiometry. Since electron bonding levels are involved, the cations exist in various valence states and hence give rise to a large number of oxides. The crystal structures are often classified by considering a cubic or hexagonal close-packed lattice of one set of ions with the other set of ions filling the octahedral or tetrahedral interstices. The actual oxide structures, however, generally show departures from such regular arrays due in part to distortions caused by packing of ions of different size and to ligand field effects. These distortions depend not only on the number of d-electrons but also on the valence and the position of the transition metal in a period or group.

In the following questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices on the basis of the above passage.

Assertion: Crystal structure of oxides of transition metals often show defects.

Reason: Ligand field effect cause distortions in crystal structures.


EΘ of Cu is + 0.34V while that of Zn is – 0.76V. Explain.


The halides of transition elements become more covalent with increasing oxidation state of the metal. Why?


Match the properties given in Column I with the metals given in Column II.

  Column I (Property) Column II (Metal)
(i)  An element which can show +8 oxidation state (a) \[\ce{Mn}\]
(ii)  3d block element that can show (b) \[\ce{Cr}\]
  upto +7 oxidation state (c) \[\ce{Os}\]
(iii)  3d block element with highest melting point (d) \[\ce{Fe}\]

Answer the following question:

Which element of the first transition series has lowest enthalpy of atomisation?


Mention any three processes where transition metals act as catalysts.


Read the passage given below and answer the following question.

Are there nuclear reactions going on in our bodies?

There are nuclear reactions constantly occurring in our bodies, but there are very few of them compared to the chemical reactions, and they do not affect our bodies much. All of the physical processes that take place to keep a human body running are chemical processes. Nuclear reactions can lead to chemical damage, which the body may notice and try to fix. The nuclear reaction occurring in our bodies is radioactive decay. This is the change of a less stable nucleus to a more stable nucleus. Every atom has either a stable nucleus or an unstable nucleus, depending on how big it is and on the ratio of protons to neutrons. The ratio of neutrons to protons in a stable nucleus is thus around 1 : 1 for small nuclei (Z < 20). Nuclei with too many neutrons, too few neutrons, or that are simply too big are unstable. They eventually transform to a stable form through radioactive decay. Wherever there are atoms with unstable nuclei (radioactive atoms), there are nuclear reactions occurring naturally. The interesting thing is that there are small amounts of radioactive atoms everywhere: in your chair, in the ground, in the food you eat, and yes, in your body.

The most common natural radioactive isotopes in humans are carbon-14 and potassium-40. Chemically, these isotopes behave exactly like stable carbon and potassium. For this reason, the body uses carbon-14 and potassium-40 just like it does normal carbon and potassium; building them into the different parts of the cells, without knowing that they are radioactive. In time, carbon-14 atoms decay to stable nitrogen atoms and potassium-40 atoms decay to stable calcium atoms. Chemicals in the body that relied on having a carbon-14 atom or potassium-40 atom in a certain spot will suddenly have a nitrogen or calcium atom. Such a change damages the chemical. Normally, such changes are so rare, that the body can repair the damage or filter away the damaged chemicals.

The natural occurrence of carbon-14 decay in the body is the core principle behind carbon dating. As long as a person is alive and still eating, every carbon-14 atom that decays into a nitrogen atom is replaced on average with a new carbon-14 atom. But once a person dies, he stops replacing the decaying carbon-14 atoms. Slowly the carbon-14 atoms decay to nitrogen without being replaced, so that there is less and less carbon-14 in a dead body. The rate at which carbon-14 decays is constant and follows first order kinetics. It has a half-life of nearly 6000 years, so by measuring the relative amount of carbon-14 in a bone, archeologists can calculate when the person died. All living organisms consume carbon, so carbon dating can be used to date any living organism, and any object made from a living organism. Bones, wood, leather, and even paper can be accurately dated, as long as they first existed within the last 60,000 years. This is all because of the fact that nuclear reactions naturally occur in living organisms.

Which are the two most common radioactive decays happening in human body?


Photographic film and plates have - au essential ingredient of


Why are all copper halides known except that copper iodide?


Give reason for the following statement:

[Ti(H2O)]3+ is coloured while [Sc(H2O)6]3+ is colourless.


Which of the following characteristics of transition metals is associated with their catalytic activity?


Consider the following standard electrode potential values:

\[\ce{Sn^{2+}_{ (aq)} + 2e^- -> Sn_{(s)}}\]; E0 = −0.14 V

\[\ce{Fe^{3+}_{ (aq)} + e^- -> Fe^{2+}_{ (aq)}}\]; E0 = +0.77 V

What is the cell reaction and potential for the spontaneous reaction that occurs?


Account for the following:

Copper has an exceptionally positive `"E"_("M"^(2+)//"M")^0` value.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×