The vapor pressure of ethanol at 25°C is 7.828 kPa. Calculate the vapor pressure in atm.

First you get 7.83 kPa = 7.83 * 10^4 Pa Then convert it to atm by using the relation 1 Pa = 9.8692 * 10^-6 atm, this gives you 7.83 kPa = 7.83 * 10^4 * 9.8692 * 10^-6 atm = 77.275836 * 10^-2 atm = 0.77275836 atm Now round to three significant digits, = 0.773 atm