19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
reacts with OH– as CrO 2CrO 2H Cr O H O -> Cr O The change in oxidation number of Cr is
CrO3 dissolves in aqueous NaOH to give (a) CrO
Na2CrO4 on treatment with lead acetate gives a precipitate. This precipitate is dried and the solid is used as a pigment for road signs and markings. The solid is known as
Acidified K2Cr2O7 on treatment with KI produces
When hydrogen peroxide is added to an acidic solution of a dichromate, the most probable product is
reacts with H+ as The change in oxidation number of Cr is
KMnO4 in an acidic medium oxidizes (a) C O to CO2 (b) N2H4 to N2 (c) HSO to SO
Which of the following is an incorrect statement ? (a)In a redox reaction in acidic medium, KMnO4 produces Mn2+ ions. (b)In a redox reaction in strongly alkaline medium, KMnO4produces MnO ions. (c)In a redox reaction …
KMnO4 in an acidic medium will not oxidize (a) (b)
is prepared by treating a solution containing Mn2+ ions with a very strong oxidizing agent such as
KMnO4 is manufactured on a large scale by (a)fusing MnO2 with KOH and then oxidizing the fused mixture with KNO3
Which of the following ions has the maximum number of unpaired d electrons ?
Which of the following is not true about the transition elements ?
Which of the following statements is correct ?
The noble character of platinum and gold is favoured by
Transition metals
Among the transition metals, the melting points of Zn, Cd and Hg are relatively low because
Which of the following elements has completely filled d orbitals (the d10 configuration) ?
The electronic configurations of the first four members of the actinide series cannot be written accurately in a regular manner because of
The last electron of a d-block element occupies the orbital
Sodium thiosulphate, Na2S2O3. 5H2O is used in photography to :
Spiegeleisen is an alloy of :
Philosopher’s wool when heated with BaO at 1100ºC gives the compound :
Give the correct order of initials T or F for the following statements. Use T if the statement is true and F if it is false. (I) Sulphide ions reacts with Na2 [Fe(CN)5(NO)] to form a purple-coloured compound Na4 [Fe(C…
The incorrect statement among the following is: (NEET 2021)