The electronic configuration of Cu(II) is 3d⁹ whereas that of Cu(I) is 3d¹⁰. Which of the following is correct?
(a) Cu(II) is more stable
(b) Cu(II) is less stable
(c) Cu(I) and Cu(II) are equally stable
(d) Stability of Cu(I) and Cu(II) depends on nature of copper salts
(a) Cu(II) is more stable
(b) Cu(II) is less stable
(c) Cu(I) and Cu(II) are equally stable
(d) Stability of Cu(I) and Cu(II) depends on nature of copper salts
(a) Cu(II) is more stable
Explanation : Cu(II) is more stable due to nuclear charge of Cu.
Explanation : Cu(II) is more stable due to nuclear charge of Cu.
Electronic configuration of a transition element X in +3 oxidation state is [Ar]3d⁵. What is its atomic number?
(a) 25
(b) 26
(c) 27
(d) 24
Explain the following :
(i) The enthalpies of atomization of transition metals are quite high.
(ii) The transition metals and many of their compounds act as good catalysts.
Metallic radii of some transition elements are given below. Which of these elements will have highest density?
Suggest reasons for the following features of transition metal chemistry :
(i) The transition metals and their compounds are usually paramagnetic.
(ii) The transition metals exhibit variable oxidation states.
Describe the preparation of potassium permanganate. How does the acidified permanganate solution react with oxalic acid ?
Write the ionic equations for the reactions.
Account for the following :
(i) CuCl₂ is more stable than Cu₂Cl₂.
(ii) Atomic radii of 4d and 5d series elements are nearly same.
(iii) Hydrochloric acid is not used in permanganate titration.
Which of the following aqueous solutions containing 10 g of solute in each case, has highest m.p.?
(a) NaCl solution
(b) KCl solution
(c) sugar solution
(d) glucose solution
The lattice site in a pure crystal cannot be occupied by __________.
(A) Molecule
(B) Ion
(C) Electron
(D) Atom
The correct order of the packing efficiency in different types of unit cells is ________.
(A) fcc < bcc < simple cubic
(B) fcc > bcc > simple cubic
(C) fcc < bcc > simple cubic
(D) bcc < fcc = simple cubic
Low concentration of oxygen in the blood and tissues of people living at high altitude is due to-
(a) low temperature
(b) low atmospheric pressure
(c) high atmospheric pressure
(d) both low temperature and high atmospheric pressure
An alcohol X when treated with hot conc. \(H_2\)\(SO_4\) gave an alkene Y with formula \(C_4\)\(H_8\). This alkene on ozonolysis gives single product with molecular formula \(C_2\)\(H_4\)O. The alcohol is
(a) butan-1-ol.
(b) butan-2-ol.
(c) 2-methylpropan-1-ol.
(d) 2,2-dimethylbutynal-1-oI.
Molecules whose mirror image is non-superimposable over them are known as chiral. Which of the following molecules is chiral in nature?
(a) 2-Bromobutane.
(b)1-Bromobutane.
(c) 2-Bromopropane.
(d) 2-Bromopropan-2-ol.
Stability of hydrides of group 16 elements
a) increases down the group
b) decreases down the group
c) all hydrides are equally stable
d) none of the above