Lab Quiz 2

Vigorous boiling of a liquid occurs only at the bottom of the liquid occurs only at the liquid surface occurs throughout the liquid none of the above answers is correct

Evaporation from a volatile liquid occurs from anywhere in the liquid only from the bottom of the liquid only from the left side of the liquid only from the surface of the liquid

While a pure liquid is boiling, its temperature rises as the liquid level drops rises as heat is added remains constant depends on the size of the heat source (e.g., candle vs. blow torch)

Consider a pure liquid at a temperature between its melting and boiling points. The molecules which evaporate into the gas phase are the ones traveling with _____ velocity. low average any value of high

At a given temperature, all molecules of a pure gas have identical molecular velocities. true false

In this experiment, the liquid's heat of vaporization is proportional to the temperature (Kelvin) depends on barometric pressure is assumed constant if 10 =< T =< 40 (°C) none of the above answers is correct

The vapor pressure of a pure liquid in a closed container depends on (Select all that apply.) other species present in the gas phase (assume no reaction with any of the other species) the surface area of the liquid the temperature of the liquid the liquid atmospheric (barometric) pressure

Select all parameters in the following list that change while you are collecting data during the experiment (Select all that apply.) moles of air in the sealed flask volume pressure of air in the sealed flask total pressure inside the flask moles of volatile liquid in the liquid phase in the sealed flask moles of volatile liquid in the gas phase in the sealed flask temperature

After the volatile liquid has been added to the Erlenmeyer flask, the total pressure in the flask equals the vapor pressure of the volatile liquid. true false

As long as some residual liquid is left after liquid-vapor equilibrium is reached, the vapor pressure of a liquid at any given temperature is an intensive property of the liquid. (in other words, at equilibrium, the vapor pressure in the flask does not depend on the quantity of liquid at the bottom of the flask). true false