Determine the mass, in grams, of 0.800 moles of Pb (1 mol of Pb has a mass of 207.2 g).

What is the ph of a 0.0010 m hno3? 1.0 3.0 4.0 5.0

Imagine that you push on a large rock. at what point does your effort change the rock’s mechanical energy?

)benzene and toluene form nearly ideal solutions. consider an equimolar solution of benzene and toluene. at 20 °c the vapour pressures of pure benzene and toluene are 9.9 kpa and 2.9 kpa, respectively. the solution is boiled by reducing the external pressure below the vapour pressure. calculate (i) the pressure when boiling begins, (ii) the composition of each component in the vapour, and (iii) the vapour pressure when only a few drops of liquid remain. assume that the rate of vaporization is low enough for the temperature to remain constant at 20 °c.