If purity level of Zn is 60% then how much Zn is needed for the reaction with dil.`H_2SO_4` to produce 1 gm `H_2`?

Which of the following is insoluble in dil. H_2SO_4 -

12.25 gm KClO_3 is heated to produe oxygen. How much quantity of Zn is required to produce hydrogen to react with the produced oxygen? (Zn = 65, K = 39, O = 16, Cl = 35.5, H = 1)

Which of the following is insoluble in dil. H_(2)SO_(4) ?

The oxidation numbers of the most electronegative element in the product obtained due to the reaction between BaO_(2) and dil. H_(2) SO_(4) are-

Brass is an alloy of Cu-Zn. A sample of brass weighing 5.793 g, when treated with excess of dil. H_2SO_4 gives 324 mi of dry H_2 at 20^@C and 750 mm pressure. What is the percentage of Cu by mass in the alloy ?

How many moles of electrons are needed for the reduction of each mole of Cr in the reaction, CrO_5+H_2​SO_4 rarr Cr_ 2(SO _4 )_ 3+H_2O+O_2 ​

I^(-) reduces SO_(4)^(2-) to H_(2)S in acidic medium as per the reaction, 8KI+5H_(2)SO_(4) to 4K_(2)SO_(4)+4I_(2)+H_(2)S+4H_(2)O to produce 34.0 g H_(2)S , volume of 0.20 (M) H_(2)SO_(4) required is-

How many mL of 96%h_2SO_4 solution is necessary to prepare one litre o.1 N h_2So_4 ?

5.5 g of a pure sample of FeS reacts with dil. H_(2)SO_4 . H_(2)S gas so produced is then completely burnt in air. Find the volume of SO_(2) thus obtained, measured at 25^(@)C and 750 mm pressure of Hg.