The normal boiling point of ethanol is 78.85 ºC and the molar enthalpy of vaporization, ΔHvap, is 71.8 kJ/mol. What is the value of ΔSsys in J/K when 3.40 mol of ethanol (l) vaporizes at 78.85 ºC?

A4.86 g piece of metal was placed in a graduated cylinder containing 15.5 ml of water. the water level rose to 17.3 ml. what is the density of the metal. i need the steps of how to solve it to so i can use a formula to work out other problems.

The solubility of barium nitrate is 9.02 g/100 g h2o at 20°c. a 15.2 g sample of barium nitrate is added to 200.0 g of water at 20°c. is the solution saturated, unsaturated, or supersaturated? a. unsaturated b. saturated c. supersaturated

Calculate the ph of a .10m nh4cl solution. the kb value for nh3 is 1.8×10^-5