Can someone answer please Determine the boiling point of water at 698.5 mm Hg?
I answered you earlier. Use the Clausius-Clapeyron equation. You will need to look up the delta H vaporization and you will also need the data that at 760 mm Hg pressure the boiling point is 100 C.
To determine the boiling point of water at 698.5 mm Hg, we can use the Clausius-Clapeyron equation, which relates the boiling point of a substance to its vapor pressure at a given temperature.
The Clausius-Clapeyron equation is given by:
ln(P1/P2) = (∆Hvap/R) * [(1/T2) - (1/T1)]
where:
P1 is the initial pressure (in this case, normal atmospheric pressure, 760 mm Hg)
P2 is the final pressure (given as 698.5 mm Hg)
∆Hvap is the enthalpy of vaporization for water (40.7 kJ/mol)
R is the ideal gas constant (8.314 J/(mol·K))
T1 is the initial temperature (the boiling point of water at normal atmospheric pressure is 100°C or 373 K)
We need to solve for T2, which represents the boiling point at the given pressure of 698.5 mm Hg.
Rearranging the equation:
ln(P2/P1) = (∆Hvap/R) * [(1/T2) - (1/T1)]
Substituting the values into the equation:
ln(698.5/760) = (40.7 * 10^3 / 8.314) * [(1/T2) - (1/373)]
Now, we can calculate T2 by rewriting the equation as:
1/T2 = [(ln(698.5/760) * 8.314) / (40.7 * 10^3)] + (1/373)
Now, let's solve this equation to find the boiling point of water at 698.5 mm Hg.
To determine the boiling point of water at 698.5 mm Hg, we can use the phase diagram for water, which shows the relationship between pressure and temperature at which water changes its physical state.
Step 1: Find the phase diagram for water
The phase diagram for water provides information on the boiling points at different pressures. You can search for an image of the phase diagram of water online.
Step 2: Locate the given pressure
On the phase diagram, locate the given pressure of 698.5 mm Hg (millimeters of mercury) on the y-axis.
Step 3: Trace horizontally
Starting from the point where the pressure line intersects with the given pressure (698.5 mm Hg), trace horizontally until you reach the curve or boundary line that represents the boiling point.
Step 4: Read the temperature
Once you reach the boundary line, read the corresponding temperature value on the x-axis. This will be the boiling point of water at 698.5 mm Hg.
Note: Make sure that the pressure and temperature units on the phase diagram match the values given in the question.
By following these steps using the phase diagram, you should be able to determine the boiling point of water at 698.5 mm Hg.