A is a binary compound of a univalent metal. `1.422 g` of A reacts completely with `0.321 g` of sulphur in an evacuated and sealed tube to give `1.743 g` of a white crystalline solid B, that forms a bydrated double salt, C with `Al_(2) (SO_(4))_(3)`. Identify A, B and C.
A is a binary compound of a univalent metal. `1.422 g` of A reacts completely with `0.321 g` of sulphur in an evacuated and sealed tube to give `1.743 g` of a white crystalline solid B, that forms a bydrated double salt, C with `Al_(2) (SO_(4))_(3)`. Identify A, B and C.
Text Solution
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Compound B forms hydrated crystals with `Al_(2)(SO_(4))_(3)`. Also, B is formed with univalent metal on heating with sulphur. Hence, compound B must has the molecular formula `M_(2)SO_(4)` and compound A must be an oxide of M which reacts with sulphur to give metal sulphate as
`A+S rarr M_(2)SO_(4)`
`:' 0.321 g` sulphur gives `1.743 g` of `M_(2)SO_(4)`
`:. 32.1 g S` (one mole) will give `174.3 g M_(2)SO_(4)`
Therefore, molar mass of `M_(2)SO_(4)=174.3 g`
`implies 174.3=2xx` Atomic weight of `M+32.1+64`
`implies` Atomic weight of `M=39`, metal is potassium `(K)`
`K_(2)SO_(4)` on treatement with aqueous `Al_(2)(SO_(4))_(3)` gives potash-alum.
`underset(B)(K_(2)SO_(4))+Al_(2)(SO_(4))_(3)+24H_(2)O rarr K_(2)SO_(4)Al_(2)underset(C)((SO_(4))_(3)).24H_(2)O`
If the metal oxide A has molecular formula `MO_(x)` two moles of it combine with one mole of sulphur to give one mole of metal sulphate as
`2KO_(x)+S rarr K_(2)SO_(4)`
`implies x=2`, i.e. `A` is `KO_(2)`.
`A+S rarr M_(2)SO_(4)`
`:' 0.321 g` sulphur gives `1.743 g` of `M_(2)SO_(4)`
`:. 32.1 g S` (one mole) will give `174.3 g M_(2)SO_(4)`
Therefore, molar mass of `M_(2)SO_(4)=174.3 g`
`implies 174.3=2xx` Atomic weight of `M+32.1+64`
`implies` Atomic weight of `M=39`, metal is potassium `(K)`
`K_(2)SO_(4)` on treatement with aqueous `Al_(2)(SO_(4))_(3)` gives potash-alum.
`underset(B)(K_(2)SO_(4))+Al_(2)(SO_(4))_(3)+24H_(2)O rarr K_(2)SO_(4)Al_(2)underset(C)((SO_(4))_(3)).24H_(2)O`
If the metal oxide A has molecular formula `MO_(x)` two moles of it combine with one mole of sulphur to give one mole of metal sulphate as
`2KO_(x)+S rarr K_(2)SO_(4)`
`implies x=2`, i.e. `A` is `KO_(2)`.
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A is a binary compound of a univalent metal. 1.422 g of A reacts completely with 0.321 g of sulphur in an evacuated and sealed tube to give 1.743 g of a white crystalline solid B, that forms a hydrated salt C, with Al_2(SO_4)_3 . Identify A, B and C.
A is a binary compound of a univalent metal. When 1.422 g of A reacts completely with 0.321 g of sulphur in an evacuated and sealed tube, 1.743 g of white crystalline solid B produced, which produces a hydrated double salt C with Al_(2)(SO_(4))_(3) . Identfy A, B and C.
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In compound A,1 g of nitrogen combines with 0.57 g oxygen. In compound B,2 g of nitrogen combines with 2.24 g oxygen. In compound C,3 g of nitrogen combines with 5.11 g oxygen. These results obey following law
In compound A,1 g of nitrogen combines with 0.57 g oxygen. In compound B,2 g of nitrogen combines with 2.24 g oxygen. In compound C,3 g of nitrogen combines with 5.11 g oxygen. These results obey following law
A
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B
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D
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If 50 ml of A_(2)B_(3) reacts completely with 200 ml of C_(2) in closed vessel according to the equation , 2A_(2)B_(3)(g)+5C_(2)(g) to 3C_(3)B_2(g)+CA_(4)(g) . The composition of the mixture of gases is :
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