Pick out the incorrect statement.A. Except nitrogen, all the elements of group 15 exist in allotropic modificationB. Only at high temperatures, greater than 1070 K, phosphorus vapours dissociates into `P_2` moleculesC. Red P is obtained by heating white phosphorus at 540-570 K in the absence of air for several hours.D. White P is more reactive, but less soluble in `CS_2` (and other organic solvents) than red P.

Pick out the incorrect statement.A. Except nitrogen, all the elements

1.	Pick out the incorrect statement.A. Except nitrogen, all the elements of group 15 exist in allotropic modificationB. Only at high temperatures, greater than 1070 K, phosphorus vapours dissociates into `P_2` moleculesC. Red P is obtained by heating white phosphorus at 540-570 K in the absence of air for several hours.D. White P is more reactive, but less soluble in `CS_2` (and other organic solvents) than red P.
Answer» Correct Answer - D White phosphorus is readily soluble in `CS_2` and other organic solvent, but red phosphorus is insoluble in these.

vii. The stability of dihalides of ` Si, Ge , Sn` and Pb increases steadily in the sequence :A. `GeX_(2) lt SiX_(2) lt SnX_(2) lt PbX_(2)`B. `SiX_(2) lt GeX_(2) lt PbX_(2) lt SnX_(2)`C. `SiX_(2) lt GeX_(2) lt SnX_(2) lt PbX_(2)`D. `PbX_(2) lt SnX_(2) lt GeX_(2) lt SiX_(2)`
When `H_2S` is passed through acidified `KMNO_4`, we getA. `K_(2)SO_(4)`B. `MnO_(2)`C. `KHSO_(3)`D. Sulphur
The`3ClO^(-)(aq.)to ClO_(3)^(-)(aq.)+2Cl^(-)(aq.)` is an example ofA. oxidation reactionB. disproportionationC. reduction reactionD. decomposition
The reaction: `ClO_(3)^(-) +I_(2) to IO_(3)^(-)+Cl_(2)`A. is possibleB. depends upon the state of productsC. is not possibleD. depends upon the temperature
In the reaction: `3Br_(2)+6OH^(Theta)rarr 5Br^(Theta)+BrO_(3)^(Theta)+3H_(2)O,Br_(2)` isA. is reducedB. is oxidizedC. disproportionatesD. disintegrate
`NaClO_(3)` is obtained by reacting `Cl_(2)` andA. cold dil. NaOHB. hot conc. NaOHC. cold `Na_(2)O_(2)`D. hot `Na_(2)O_(2)`
Which of the following is acidic oxides ?A. `HClSO_(4)`B. `MgO`C. `Al_(2)O_(3)`D. `CaO`
Which of the following is more acidic oxyacid ?A. `HClO_(4)`B. `HClO`C. `HClO_(3)`D. `HClO_(2)`
Oxygen orm acidic oxide withA. CaB. NaC. SD. K
Of the following, the most acidic isA. `As_(2)O_(3)`B. `P_(2)O_(3)`C. `Sb_(2)O_(3)`D. `Bl_(2)O_(3)`