Amorphous boron is extracted from borax by the following steps : `"Borax" overset((A))rarr H_(3) BO_(3) overset("Heat")rarr B_(2) O_(3) overset((B)) rarr "Boron" (A) and (B) are` (a) `H_(2) SO_(4), Al` (b) `HCl`, Carbon ( c) `H_(2) SO_(4), Mg` (d) `HCl, Fe`.A. `H_(2)SO_(4),Al`B. `HCl`,carbonC. `H_(2)SO_(4),Mg`D. `HCl,Fe`

Amorphous boron is extracted from borax by the following steps : `"Bor

1.	Amorphous boron is extracted from borax by the following steps : `"Borax" overset((A))rarr H_(3) BO_(3) overset("Heat")rarr B_(2) O_(3) overset((B)) rarr "Boron" (A) and (B) are` (a) `H_(2) SO_(4), Al` (b) `HCl`, Carbon ( c) `H_(2) SO_(4), Mg` (d) `HCl, Fe`.A. `H_(2)SO_(4),Al`B. `HCl`,carbonC. `H_(2)SO_(4),Mg`D. `HCl,Fe`
Answer» Correct Answer - C `Na_(2)B_(4)O_(7)+H_(2)SO_(4)+5H_(2)OtoNa_(2)SO_(4)+4H_(3)BO_(3)` `2H_(3)BO_(3)toB_(2)O_(3)+3H_(2)O` `B_(2)O_(3)+3Mg to 2B+3MgO`

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)`