Which of the following is most needed for cosmetologist to study the age of the universe

)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.

For the reaction c6h14(g) & longrightarrow; c6h6(g) + 4h2(g), δp(h2)/δt was found to be 2.5 x 10-2 atm/s, where δp(h2) is the change in pressure of hydrogen. determine δp(c6h14)/δt for this reaction at the same time.

Astudent states that 9.0 g of baking soda will form an unsaturated solution in 100 g of water. what do you need to know to decide whether this statement is correct? a. the temperature of the water and the molar mass of baking soda b. the percent by volume of the solution and the solubility of baking soda c. the temperature of the water and the solubility of baking soda at that temperature