On heating `4.9g` `KClO_(3)`, its mass is reduced by `0.384g`. Calculate the percentage of original `KClO_(3)` sample, that has been decomposed.

Calculate the percentage composition of each element in Potassium chlorate, KClO_3 .

A mixture of CaCO_(3) and MgCO_(3) weighing 1.84 g on heating left a residue weighing 0.96 g . Calculate the percentage of each in the mixture.

A mixture of CaCO_(3) and MgCO_(3) weighing 1.84 g on heating left a residue weighing 0.96 g . Calculate the percentage of each in the mixture.

A sample containing only CaCo_(3) and MgCo_(3) is ignited to CaO and MgO. The mixture of oxides produced weight exactly half as much as the original sample. Calculate the percentages of CaCO_(3) and MgCO_(3) (by mass) in the sample.

A 0.24 g sample of compound of oxygen and boron was found by analysis to contain 0.096 g of boron and 0.144 g of oxygen. Calculate the percentage composition of the compound by weight.

A 1.0 g sample of KCIO_3 was heated under such conditions that a part of it decomposed according to the equation: (i) 2KCIO_3 to 2KCI + 3O_2 and the remaining underwent a change according to the equation (ii) 4KCIO_3 to 3KClO_4 + KCI . If the amount of oxygen evolved was 146.8 mL at S.T.R, calculate the percentage by weight of KClO_4 in the residue.

O_(2) is evolved by heating KClO_(3) using MnO_(2) as a catalyst 2KClO_(3) overset(MnO_(2))to 2KCl+3O_(2) Calculate the mass of KClO_(3) required to produce 6.72 litre of O_(2) at S.T.P. [atomic masses of K = 39, Cl = 35.5, O = 16).

20 g mixture of Na_(2)CO_(3) and CaCO_(3) is gently heated. On heating this sample produces 2.24 litre of CO_(2) at STP. Calculate the % weight of Na_(2)CO_(3) in that sample.

A bcc element (atomic mass 65) has cell edge of 420 pm. Calculate its density in g cm^(-3) .

2 g sample of KClO_(3) was heated under such conditions that a part of it decomposed according to the equation : 2KClO_(3) rarr 2KCl + 3O_(2) and the remaining underwent change according to the equation : 4KClO_(3)rarr 3KClO_(4)+KCl If the amount of O_(2) evolved was 146.8 ml at S.T.P., calculate the % by weight of KClO_(4) in the reside.