English

Science (English Medium) Class 12 - CBSE Important Questions

Advertisements
[object Object]
[object Object]
Subjects
Popular subjects
Topics

Please select a subject first

Advertisements
Advertisements
< prev  2861 to 2880 of 6295  next > 

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: General 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: General 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: Some Important Compounds of Transition Elements - Oxides and Oxoanions of Metals

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: General 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: General 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: General 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: Some Important Compounds of Transition Elements - Oxides and Oxoanions of Metals

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: General 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: General Properties of the Transition Elements (d-block)

Give two similarities in the properties of Sc and Zn.

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

What is actinoid contraction?

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: F-block Elements >> The Actinoids

What causes actinoid contraction?

Appears in 1 question paper
Chapter: [4] d-block and f-block Elements
Concept: F-block Elements >> The Actinoids

What is the oxidation state of chromium in chromate ion and dichromate ion?

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

Write the ionic equation for reaction of KI with acidified KMnO4.

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

Write the formula of Tetraminodichloroplatinum (IV) chloridex.

Appears in 1 question paper
Chapter: [5] Coordination Compounds
Concept: Nomenclature of Coordination Compounds - Formulas of Mononuclear Coordination Entities

Write the IUPAC name of 

Appears in 1 question paper
Chapter: [5] Coordination Compounds
Concept: Nomenclature of Coordination Compounds - Naming of Mononuclear Coordination Compounds

Write the dispersed phase and dispersion medium of the following colloidal systems: 

(i) Smoke

(ii) Milk

Appears in 1 question paper
Chapter: [5] Surface Chemistry
Concept: Catalysis >> Enzyme Catalysis

What are lyophilic and lyophobic colloids ? Which of these sols can be easily coagulated on the addition of small amounts of electrolytes?

Appears in 1 question paper
Chapter: [5] Surface Chemistry
Concept: Purification of Colloidal Solution

What are lyophilic and lyophobic colloids ? Which of these sols can be easily coagulated on the addition of small amounts of electrolytes?

Appears in 1 question paper
Chapter: [5] Surface Chemistry
Concept: Purification of Colloidal Solution
< prev  2861 to 2880 of 6295  next > 
Advertisements
Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×