Compared to water, hydrogen sulphide is thermally less stable, stronger acid and better reductant. Substantiate. 

An aqueous solution of a substance gives a white precipitate on treatment with dilute hydrochloric acid, which dissolves on heating. When hydrogen sulphide is passed through the hot acidic solution, a black precipitate is obtained. The substance is a :

(A): Hydrogen iodide is most stable among hydrogen halides (R): Iodide is most powerful reductant among halides.

Passage-I : Metallic sulphates can be obtained by reacting the metals (above hydrogen in ECS), or its oxide, hydroxide or carbonate with dil. H_(2)SO_(4) . Group IA metals also form hydrogen sulphates which can be isolated in solid. In general metal sulphates are soluble in water and crystallize with water of crystallization. Sulphates are thermally more stable than nitrates. Select the stable hydrogen sulphate which can be obtained in solid state:

The following statements about electro chemical series are i) the metals occupying top positions in the series do not liberate hydrogen with dilute acids ii) the substances which are stronger reducing agents and stronger oxidising agents are placed below & top respectively iii) a metal higher in the series will displace the metal from its solution which is lower in the series iv) various electrodes are arranged in a series in the descending order of their potentials The correct statements are The correct statements are

Passage-I : Metallic sulphates can be obtained by reacting the metals (above hydrogen in ECS), or its oxide, hydroxide or carbonate with dil. H_(2)SO_(4) . Group IA metals also form hydrogen sulphates which can be isolated in solid. In general metal sulphates are soluble in water and crystallize with water of crystallization. Sulphates are thermally more stable than nitrates. Select the thermally more stable salt from given pairs: A) Al_(2)(SO_(4))_(3)" "B)Al(NO_(3))_(3)" "C) Ca(NO_(3))_(2)" "D) CaSO_(4)" "E )FeSO_(4)" "F) Fe(NO_(3))_(2)

Passage-I : Metallic sulphates can be obtained by reacting the metals (above hydrogen in ECS), or its oxide, hydroxide or carbonate with dil. H_(2)SO_(4) . Group IA metals also form hydrogen sulphates which can be isolated in solid. In general metal sulphates are soluble in water and crystallize with water of crystallization. Sulphates are thermally more stable than nitrates. Select the sulphate which is water soluble:

Passage-I : Metallic sulphates can be obtained by reacting the metals (above hydrogen in ECS), or its oxide, hydroxide or carbonate with dil. H_(2)SO_(4) . Group IA metals also form hydrogen sulphates which can be isolated in solid. In general metal sulphates are soluble in water and crystallize with water of crystallization. Sulphates are thermally more stable than nitrates. Which metal sulphate will decompose into SO_(3) and metal oxide when heated:

Passage-I : Metallic sulphates can be obtained by reacting the metals (above hydrogen in ECS), or its oxide, hydroxide or carbonate with dil. H_(2)SO_(4) . Group IA metals also form hydrogen sulphates which can be isolated in solid. In general metal sulphates are soluble in water and crystallize with water of crystallization. Sulphates are thermally more stable than nitrates. When BaCl_(2) solution is added in aq. Solution of NaHSO_(4) a white ppt. is obtained which is of:

The most acidic and thermally stable hydride of chalcogens are respectively