A compound H₂X with molar weight of 80g is dissolved in a solvent having density of 0.4 gml^–1 . Assuming no change in volume upon dissolution, the molality of a 3.2 molar solution is

29.2 % (w/w) HCl stock solution has density of 1.25 g mL^-1 . The molecular weight of HCl is 36.5 g mol^-1 . The volume (mL) of stock solution required to prepare a 200 mL solution of 0.4 M HCl is

A student performs a titration with different burettes and finds titre values of 25.2 mL, 25.25 mL, and 25.0 mL. The number of significant figures in the average titre value is

Silver (atomic weight = 108 g mol^-1) has a density of 10.5 g.cm^-3. The number of silver atoms on a surface of area 10^-12 m² can be expressed in scientific notation as y $$\times$$ 10^x. The value of x is?