Calculate the mass of potassium chlorate required to librate` 6.72 dm^3` of oxygen at STP, molar mass of potassium chlorate is `122.5 g /mol`.

Calculate the mass of sodium acetate (CH_3COONa) required to make 500 mL of 0.375 molar aqueous solution. Molar mass of sodium acetate is 52.0245 g mol^-1

Calculate the number of moles and molecules of ammonia present in 5.6dm^3 of its volume at STP.

Calculate the volume in litres of 49.8 g of HCl gas at STP (Molar mass of HCl =36.5 g mol^-1) .

Calculate the volume in litres occupied by 7.4g of ammonia at STP(molar mass of NH_3 = 17 g mol^-1 ).

3.49 g of ammonia at STP occupies volume of 4.48 dm^3 . Calculate molar mass of ammonia

Calculate the mass in grams of an impurity ofmolar mass 100 g mol^(-1) which would be required to raise the boiling point of 50 g of chloroform by 0.30 K (Kb for chloroform 3.63 K kg mol^(-1)) .

Two electrolytic cells one containing AlCl_3 solutionand the other ontaining ZnSO_4 solution are connected in series. The same quantity of electricity is passed between the cells, Calculate the amount of Zn deposited in ZnSO_4 cell if 1.2 g of AI are deposited in AlCl_3 cell. The molar masses of Al and Zn are 27 g mol^(-1) and 65.4 g mol^(-1) respectively.

Calculate the horizontal force required to just move a block of mass 20kg resting on a horizontalsurface (mu_s = 0.3 , g= 9.8m//s^2)

Calculate the horizontal force required to just move a block of mass 40kg resting on the horizontal surface given (mu_s = 0.3) , g = 9.8 m//s^2