Using the apparatus described in the figure below, a 200.0-mL flask at 99°C and a pressure of 734 mmHg is filled with the vapor of a volatile (easily vaporized) liquid. The mass of the substance in the flask is 0.946 g. What is the molecular weight of the liquid? Boiling water Sample (should evaporate completely) Vapor of sample
Ideal and Real Gases
Ideal gases obey conditions of the general gas laws under all states of pressure and temperature. Ideal gases are also named perfect gases. The attributes of ideal gases are as follows,
Gas Laws
Gas laws describe the ways in which volume, temperature, pressure, and other conditions correlate when matter is in a gaseous state. The very first observations about the physical properties of gases was made by Robert Boyle in 1662. Later discoveries were made by Charles, Gay-Lussac, Avogadro, and others. Eventually, these observations were combined to produce the ideal gas law.
Gaseous State
It is well known that matter exists in different forms in our surroundings. There are five known states of matter, such as solids, gases, liquids, plasma and Bose-Einstein condensate. The last two are known newly in the recent days. Thus, the detailed forms of matter studied are solids, gases and liquids. The best example of a substance that is present in different states is water. It is solid ice, gaseous vapor or steam and liquid water depending on the temperature and pressure conditions. This is due to the difference in the intermolecular forces and distances. The occurrence of three different phases is due to the difference in the two major forces, the force which tends to tightly hold molecules i.e., forces of attraction and the disruptive forces obtained from the thermal energy of molecules.
![Using the apparatus described in the figure below, a 200.0-mL flask at 99°C and a pressure of 734 mmHg is filled with the vapor of a volatile (easily vaporized) liquid. The mass of the substance in the flask is 0.946 g. What is the molecular weight of the liquid?
**Apparatus Description:**
- The diagram shows a setup with a boiling water bath.
- A flask is submerged in boiling water and contains the sample that should evaporate completely.
- The flask is connected to a device that measures the temperature and pressure of the vapor.
- Labels indicate the presence of boiling water and vapor of the sample within the flask.
**Equation for Calculation:**
To calculate the molecular weight of the vaporized liquid in the flask, use the following formula:
\[ \text{Molecular Weight} = \frac{g \cdot R \cdot T}{P \cdot V} \]
Where:
- \( g = 0.946 \text{ g (mass of the vapor)} \)
- \( R = 0.0821 \text{ L atm / (mol K)} \) (Ideal gas constant)
- \( T = (99 + 273) \text{ K} \) (Temperature in Kelvin)
- \( P = 734 \text{ mmHg} \times \frac{1 \text{ atm}}{760 \text{ mmHg}} \)
- \( V = 0.200 \text{ L (volume of the flask)} \)
Enter the calculated molecular weight in the provided field (in amu).](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2Ffcaf0374-1550-4ffb-84ad-720668c0d5ec%2Fc9527f7e-bf14-4255-83c7-42ae7eba00ac%2Fipkdtym_processed.png&w=3840&q=75)
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