Advertisements
Advertisements
प्रश्न
When a brown compound of manganese (A) is treated with \[\ce{HCl}\] it gives a gas (B). The gas taken in excess, reacts with \[\ce{NH3}\] to give an explosive compound (C). Identify compounds A, B and C.
Advertisements
उत्तर
The compounds A, B and C are as follows:
A = \[\ce{MnO2}\], B = \[\ce{Cl2}\], C = \[\ce{NCl3}\]
The reactions are explained as under:
\[\ce{\underset{(A)}{MnO2} + 4HCl -> MnCl2 + \underset{(B)}{Cl2} + 2H2O}\]
\[\ce{\underset{(Excess)}{3Cl2} + NH3 -> \underset{(C)}{NCl3} + 3HCl}\]
APPEARS IN
संबंधित प्रश्न
In the series Sc (Z = 21) to Zn (Z = 30), the enthalpy of atomization of zinc is the lowest, i.e., 126 kJ mol−1. Why?
Why is the highest oxidation state of a metal exhibited in its oxide or fluoride only?
How would you account for the following:
Of the d4 species, Cr2+ is strongly reducing while manganese (III) is strongly oxidising.
Calculate the number of unpaired electrons in the following gaseous ions:
Mn3+, Cr3+, V3+ and Ti3+. Which one of these is the most stable in an aqueous solution?
An antifriction alloy made up of antimony with tin and copper, which is extensively used in machine bearings is called _______.
(A) Duralumin
(B) Babbitt metal
(C) Spiegeleisen
(D) Amalgam
The paramagnetic character in the 3d-transition series elements increases up to Mn and then decreases.
How is potassium dichromate prepared from chrome iron ore?
Metallic radii of some transition elements are given below. Which of these elements will have highest density?
| Element | \[\ce{Fe}\] | \[\ce{Co}\] | \[\ce{Ni}\] | \[\ce{Cu}\] |
| Metallic radii/pm | 126 | 125 | 125 | 128 |
Generally transition elements form coloured salts due to the presence of unpaired electrons. Which of the following compounds will be coloured in solid-state?
Explain why does colour of KMnO4 disappear when oxalic acid is added to its solution in acidic medium.
Assertion: \[\ce{Cu^2+}\] iodide is not known.
Reason: \[\ce{Cu^2+}\] oxidises \[\ce{I^-}\] to iodine.
Identify the metal and justify your answer.
\[\ce{MO3F}\]
On the basis of the figure given below, answer the following questions:
- Why Manganese has lower melting point than Chromium?
- Why do transition metals of 3d series have lower melting points as compared to 4d series?
- In the third transition series, identify and name the metal with the highest melting point.
Which of the following is non-metallic?
The orientation of an atomic orbital is governed by
The standard electrode potentials of four elements A, B, C and D are – 3.05, – 1.66, – 0.40 and + 0.80. The highest chemical reactivity will be exhibited by
Match List - I with List - II.
| List - I | List - II | ||
| (A) | [Fe(CN)6]3− | (i) | 5.92 BM |
| (B) | [Fe(H2O)6]3+ | (ii) | 0 BM |
| (C) | [Fe(CN)6]4− | (iii) | 4.90 BM |
| (D) | [Fe(H2O)6]2+ | (iv) | 1.73 BM |
Choose the correct answer from the options given below.
Give reasons for the following statement:
Transition metals and most of their compounds show paramagnetic behaviour.
The number of terminal oxygen atoms present in the product B obtained from the following reactions is:
\[\ce{FeCr2O4 + Na2CO3 + O2 -> A + Fe2O3 + CO2}\]
\[\ce{A + H^+ -> B + H2O + Na^+}\]
Give a reason for the following:
Transition metals possess a great tendency to form complex compounds.
