Find acetonitrile-water vapor-liquid equilibrium data at 1 atm in the following paper: blackford, d. s; york, r. (1965). vapor-liquid equilibria of the system acrylonitrile-acetonitrile- water. j. chem. eng. data 10,313-318. (a) plot the vapor-liquid equilibrium data for the acetonitrile-water system as a y-x plot. (b) if the acetonitrile vapor mole fraction is 0.58 in a flash drum operating at 1.0 atm, what is the acetonitrile liquid mole fraction? (c) what are the values (y/x) at 1.0 atm for acetonitrile and water at an acetonitrile liquid mole fraction of 0.20? (d) if a feed containing 40.0 mol% acetonitrile is introduced to a flash distillation reactor operating at (v/f) = 0.65 and 1.0 atm, what is the temperature of the flash drum? what are the vapor and liquid phase mole fractions of acetonitrile?

part 1: the half-life of the element is 22 years.

part 2: it will take 132.02 year for the sample to decay from 308.0 g to 4.8125 g.

explanation:

part 1: there are two ways to determine the half life time.

first way: the half life time can be determined directly from its definition as it is the time required for the sample to decay to its half concentration.

from the data the initial concentration was 45.0 g and decayed to its half value (22.5 g) in 22.0 years.

second way: the radio active decay is considered first order reaction so we can use the laws of first order reactions.

k = (1/t) ln (a/a-x), where k is the rate constant of the reaction,

t is the time of the reaction

a is the initial concentration of the reactant

a-x is the remaining concentration at time (t)

a = 45.0 g the initial concentration at t = 0 year.

at t = 22 year, a-x = 22.5 g

then k = (1/22 year) ln (45.0 g/ 22.5 g) = 0.0315 year-1.

the half-life time (t1/2) = ln 2/ k = 0.693/ k =0.693/ 0.0315 = 22 years.

part 2:

using the same law k = (1/t) ln (a/a-x),

using the given data; a = 308.0 g and a-x = 4.8125 g and the calculated k from the part 1 (k = 0.0315 year-1)

t = (1/k) ln (a/a-x) = (1/0.0315) ln (308.0/ 4.8125) = 132.02 years

gold is my favorite solid.