Which of the following describes an endothermic reaction? a. wood burns in a campfire. b. the shell of an egg breaks when dropped. c. a balloon stretches as air is blown into it. d. batter becomes a pancake when heated.

How is the shape of the poem “peer” connected to its meaning?

Which of the following are correct values for the ideal gas laws constant r

)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.