Question 1.Which statement is generally true regarding atornic radius?" A. It remains constant within a period,
O B. It decreases from top to bottom within a group.
O C. It increases from left to right across a period.
D. It decreases from left to right across a period

)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.

Which one of the following bonds would you expect to be the most polar? a) b–h b) n–h c) p–h d) al–h e) c–h

The density of the solid phase of a substance is 0.90 g/cm3 and the density of the liquid phase is 1.0 g/cm3. a large increase in pressure will a. lower the freezing point b. raise the freezing point c. lower the boiling point d. raise the triple point e. lower the triple point