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
(a) 25
(b) 26
(c) 27
(d) 24
(b) 26
Explanation : It is formed by the loss of 3 electrons, the configuration of element X is [Ar] 3d⁶ 4s². Therefore, Atomic number = 26.
Explanation : It is formed by the loss of 3 electrons, the configuration of element X is [Ar] 3d⁶ 4s². Therefore, Atomic number = 26.
Metallic radii of some transition elements are given below. Which of these elements will have highest density?
What are the transition elements ? Write two characteristics of the transition elements.
Write the formula of an oxo-anion of Manganese (Mn) in which it shows the oxidation state equal to its group number.
Write the formula of an oxo-anion of Chromium (Cr) in which it shows the oxidation state equal to its group number.
Explain the following observation :
Most of the transition metal ions exhibit characteristic colour in aqueous solution.
Describe the oxidising action of potassium dichromate and write the ionic equations for its reaction with (i) an iodide (ii) H₂S.
When Cu²⁺ ion is treated with KI, a white precipitate is formed. Explain the reaction with the help of chemical equation.
Which of the following is an amorphous solid?
(A) Graphite (G)
(B) Quartz glass (SiO2)
(C) Chrome alum
(D) Silicon carbide (SiC)
Metallic radii of some transition elements are given below. Which of these elements will have highest density?
Interstitial compounds are formed when small atoms are dropped under the curved lattice of metals. Which of the following is not the characteristics property of interstitial compounds?
(A) They have high melting points in to pure metals
(B) They are very hard
(C) They retain metallic Conductivity
(D) They are chemically very reactive
Consider the figure and mark the correct option.
(a) water will move from side (A) to side (B) if a pressure lower than osmotic pressure is applied on piston (B).
(b) water will move from side (B) to side (A) if a pressure greater than osmotic , pressure is applied on piston (B).
(c) water will move from side (B) to side (A) if a pressure equal to osmotic pressure is applied on piston (B).
(d) water will move from side (A) to side (B) if pressure equal to osmotic pressure is applied on piston (A).
A Grignard reagent may be made by reacting magnesium with
a) Methyl amine.
b) Diethyl ether.
c) Ethyl iodide.
d) Ethyl alcohol.
The osmotic pressure of a solution is directly proportional to
(a) the molecular concentration of the solute.
(b) the absolute temperature at a given concentration.
(c) the lowering of vapour pressure.
(d) all the above.
Chlorine water on standing loses its yellow colour due to the formation of
a) Cl and HOCl.
b) HCl and HOCl.
c) HOCl and \(HOCl_2\).
d) HCl and \(HOCl_2\).