हिंदी

Science (English Medium) कक्षा १२ - CBSE Important Questions for Chemistry

Advertisements
विषयों
अध्याय
विषयों
मुख्य विषय
अध्याय
Advertisements
Advertisements
Chemistry
< prev  821 to 840 of 1307  next > 

Which one among the following metals of the 3d series has the lowest melting point?

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

Which of the following transition metals shows +1 and +2 oxidation states?

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

Assertion (A): Transition metals show their highest oxidation state with oxygen.

Reason (R): The ability of oxygen to form multiple bonds to metals.

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

In the two tetrahedral structures of dichromate ion, ______.

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Important Compounds of Transition Elements

Complete the following reaction and justify that it is a disproportionation reaction:

\[\ce{3MnO^{2-}4 + 4H^+ -> \underline{}\underline{}\underline{}\underline{} + \underline{}\underline{}\underline{}\underline{} + 2H2O}\]

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

The given graph shows the trends in melting points of transition metals:

Explain the reason why Cr has the highest melting point and manganese (Mn) has a lower melting point.

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

Consider the following standard electrode potential values:

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

\[\ce{MnO^{-4}_{ (aq)} + 8H^+ + 5e^- -> Mn^{2+}_{ (aq)} + 4H2O_{(l)}}\], E0 = +1.51 V

What is the cell potential for the redox reaction?

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

Which of the following ions has the electronic configuration 3d6?
(Atomic number: Mn = 25, Co = 27, Ni = 28)

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

A transition element X has an electronic configuration [Ar]4s23d3. Predict its likely oxidation states.

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

Complete the reaction mentioning all the products formed:

\[\ce{2KMnO4 ->[\Delta]}\]

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Important Compounds of Transition Elements

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?

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

Write the number of unpaired electrons in Cr3+.
(Atomic number of Cr = 24)

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

Complete the reaction mentioning all the products formed:

\[\ce{Cr2O^{2-}7 + 3H2S + 8H^+ ->}\]

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Important Compounds of Transition Elements

Account for the following:

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

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

Account for the following:

Eu2+ with electronic configuration [Xe]4f76s2 is a strong reducing agent.

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

Match the properties with the elements of 3d series:

(i) lowest enthalpy of atomisation (p) Sc
(ii) shows maximum number of oxidation states (q) Mn
(iii) transition metal that does not
form coloured compounds
(r) Zn
    (s) Ti
Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Electronic Configurations of the d-block Elements

The trend of which property is represented by the following graph?

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

Which of the following ions will have a magnetic moment value of 1.73 BM.

\[\ce{Sc^3+, Ti^3+, Ti^2+, Cu^2+, Zn^2+}\]

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Important Compounds of Transition Elements

In order to protect iron from corrosion, which one will you prefer as a sacrificial electrode, Ni or Zn? Why? (Given standard electrode potentials of Ni, Fe and Zn are -0.25 V, -0.44 V and -0.76 V respectively.)

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)

The second ionization enthalpies of chromium and manganese are 1592 and 1509 kJ/mol respectively. Explain the lower value of Mn.

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: Physical Properties of the Transition Elements (d-block)
< prev  821 to 840 of 1307  next > 
Advertisements
Advertisements
CBSE Science (English Medium) कक्षा १२ Important Questions
Important Questions for CBSE Science (English Medium) कक्षा १२ Biology
Important Questions for CBSE Science (English Medium) कक्षा १२ Chemistry
Important Questions for CBSE Science (English Medium) कक्षा १२ Computer Science (C++)
Important Questions for CBSE Science (English Medium) कक्षा १२ Computer Science (Python)
Important Questions for CBSE Science (English Medium) कक्षा १२ English Core
Important Questions for CBSE Science (English Medium) कक्षा १२ English Elective - NCERT
Important Questions for CBSE Science (English Medium) कक्षा १२ Entrepreneurship
Important Questions for CBSE Science (English Medium) कक्षा १२ Geography
Important Questions for CBSE Science (English Medium) कक्षा १२ Hindi (Core)
Important Questions for CBSE Science (English Medium) कक्षा १२ Hindi (Elective)
Important Questions for CBSE Science (English Medium) कक्षा १२ History
Important Questions for CBSE Science (English Medium) कक्षा १२ Informatics Practices
Important Questions for CBSE Science (English Medium) कक्षा १२ Mathematics
Important Questions for CBSE Science (English Medium) कक्षा १२ Physical Education
Important Questions for CBSE Science (English Medium) कक्षा १२ Physics
Important Questions for CBSE Science (English Medium) कक्षा १२ Political Science
Important Questions for CBSE Science (English Medium) कक्षा १२ Psychology
Important Questions for CBSE Science (English Medium) कक्षा १२ Sociology
Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×