The method for collecting a certain gas is determined by the solubility and density of the gas.
Just out of curiosity, take a glass of water and blow air into it through a straw. You will notice that as you blow, air bubbles will form inside the water, and then these bubbles eventually rise to the surface of the water and burst. Why do these bubbles move upwards? The obvious answer to this is that because the air inside the bubble is lighter than water, it rises. This very same concept is used in laboratories by scientists whenever they have to measure the volume or pressure of the gas that is formed during a reaction. Let's learn more about this in more detail.
Throughout chemical processes, gases can occasionally be created. We can learn more about the reaction that took place by collecting and measuring the amounts of gas created, and we can also utilize this as a reactant in another reaction if we collect and measure the volumes of gas produced.
The method for collecting a certain gas is determined by the following factors:
- Solubility- refers to a substance's capacity to dissolve in water
- Density- refers to how "heavy" it is in comparison to air.
The following are three popular ways for collecting a gas sample:
1. Displacement of Water
2. Upwards Delivery
3. Downwards Delivery
1. Why is oxygen collected by the downward displacement of water?
Because oxygen is somewhat heavier than air, it is gathered by the downward displacement of water rather than by air. Air has a vapor density of 14.4, while oxygen has a vapor density of 16. It's also water-soluble to a lesser extent. As a result, it does not collect in the air.
2. Which gas cannot be collected by displacement of water?
Gases that dissolve in water are unable to be collected over water. Carbon dioxide, carbon monoxide, sulphur dioxide, methane, ethylene, and chlorine are among the examples.
3. What are the methods of collecting gases?
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