The partial pressure of oxygen in the alveoli of the lungs is -
- equal to that in the blood
- more than that in the blood
- less than that in the blood
- less than that of carbon dioxide
The Correct Option is B
Approach Solution - 1
Partial Pressure of Oxygen in Alveoli and Blood
The partial pressure of oxygen (\( PO_2 \)) in the alveoli of the lungs is less than that in oxygenated blood. In normal conditions, the \( PO_2 \) in the alveoli is about 104 mmHg, while the \( PO_2 \) in oxygenated blood is approximately 95 mmHg.
Alveolar Oxygen Partial Pressure:
The partial pressure of oxygen in the alveolar air is 104 mmHg. This refers to the oxygen pressure in the air present within the alveoli of the lungs. This pressure is the average \( PO_2 \) in the alveoli where oxygen is exchanged with carbon dioxide during respiration.
Variation in Partial Pressure:
The partial pressure of oxygen in the alveoli can vary depending on factors such as changes in altitude and specific conditions (e.g., respiratory diseases, lung function, or atmospheric conditions).
Approach Solution -2
Answer: more than that in the blood
Explanation:
The partial pressure of oxygen in the alveoli is higher than in the blood because oxygen is constantly being diffused from the alveoli (where the partial pressure of oxygen is higher) into the blood. This is the process of oxygenation that occurs during respiration.
- In the alveoli, the partial pressure of oxygen is typically around 100 mmHg, while in the venous blood returning from the body, the partial pressure of oxygen is around 40 mmHg.
- This difference in partial pressures allows oxygen to diffuse from the alveoli into the blood, where it binds to hemoglobin in red blood cells for transport to tissues.
- The partial pressure of oxygen in the alveoli being higher than that in the blood is crucial for the efficient exchange of gases during respiration.
Top Questions on Partial pressure
The correct order of boiling points of hydrogen halides is:
- TS EAMCET - 2024
- Chemistry
- Partial pressure
- A container contains 1g H₂ gas and 1g O2 gas. What is the ratio of partial pressure of H₂ and O₂ (PH2/PO2)?
- JEE Main - 2024
- Chemistry
- Partial pressure
At T(K), 0.1 moles of a non-volatile solute was dissolved in 0.9 moles of a volatile solvent. The vapour pressure of pure solvent is 0.9 . What is the vapour pressure (in ) of the solution?
- TS EAMCET - 2024
- Chemistry
- Partial pressure
The reaction:
\[ \text{H}_2\text{O}(g) + \text{Cl}_2\text{O}(g) \rightleftharpoons 2 \text{HOCl}(g) \]
is allowed to attain equilibrium at 400K. At equilibrium, the partial pressures are given as:
- \( P_{\text{H}_2\text{O}} = 300 \) mm Hg
- \( P_{\text{Cl}_2\text{O}} = 20 \) mm Hg
- \( P_{\text{HOCl}} = 60 \) mm Hg
The value of \( K_p \) for the reaction at 400K is:
\[ K_p = \frac{P_{\text{HOCl}}^2}{P_{\text{H}_2\text{O}} \cdot P_{\text{Cl}_2\text{O}}} \]
- KEAM - 2024
- Chemistry
- Partial pressure
- The partial pressure of the gas in vapour phase (P) is proportional to the mole fraction of the gas (x) in the solution. It is expressed as P - KHx.
KH stands for-- CUET (UG) - 2023
- Chemistry
- Partial pressure
Questions Asked in NEET exam
- A wire of resistance \(R\) is cut into 8 equal pieces. From these pieces, two equivalent resistances are made by adding four of these together in parallel. Then these two are added in series. The net effective resistance of the combination is:
- NEET (UG) - 2025
- Resistance
- Consider the diameter of a spherical object being measured with the help of a Vernier Callipers. Suppose its 10 Vernier Scale Divisions (V.S.D.) are equal to its 9 Main Scale Divisions (M.S.D.). The least count in the M.S. is 0.1 cm and the zero of V.S. is at -0.1 cm when the jaws of Vernier callipers are closed. If the main scale reading for the diameter is \(M = 5\) cm and the number of coinciding vernier division is 8, the measured diameter after zero error correction, is:
- NEET (UG) - 2025
- Measurement of length
- A photon and an electron (mass \(m\)) have the same energy \(E\). The ratio \( \frac{\lambda_{\text{photon}}}{\lambda_{\text{electron}}} \) of their de Broglie wavelengths is: (\(c\) is the speed of light)
- NEET (UG) - 2025
- Dual nature of radiation and matter
A bob of heavy mass \(m\) is suspended by a light string of length \(l\). The bob is given a horizontal velocity \(v_0\) as shown in figure. If the string gets slack at some point P making an angle \( \theta \) from the horizontal, the ratio of the speed \(v\) of the bob at point P to its initial speed \(v_0\) is :
- NEET (UG) - 2025
- Pendulums
- De-Broglie wavelength of an electron orbiting in the \(n = 2\) state of hydrogen atom is close to (Given Bohr radius = 0.052 nm):
- NEET (UG) - 2025
- de broglie hypothesis
Concepts Used:
Partial Pressure
Partial Pressure is defined as if a container filled with more than one gas, each gas exerts pressure. The pressure of anyone gas within the container is called its partial pressure.
Dalton’s Law of Partial Pressure:
According to Dalton’s law of partial pressures, the total pressure exerted by the mixture of gases is the sum of the partial pressure of every existing individual gas, and every gas is assumed to be an Ideal gas.
Ptotal = P1 + P2 + P3 …
Where P1, P2, P3 are the partial pressures of gas 1, gas 2, and gas 3. Since every gas has an independent behavior, the ideal gas law is used to find the pressure of that gas if its number of moles, the volume of container and temperature is known.