When you fill a glass of water from faucet and then let the sit undisturbed for 2 hours will see small bubbles sticking to what are why did they form?

When you fill a glass of water from the tap and let it sit undisturbed for two hours, you may notice small bubbles sticking to the sides of the glass. These bubbles are formed due to the dissolved gases present in the water, which come out of solution and form bubbles when the water is left undisturbed. The most common dissolved gases in tap water are oxygen and nitrogen.

As water flows through pipes and comes out of the faucet, it picks up air and dissolved gases from the environment. When the water is still, these gases start to come out of solution and form tiny bubbles. The bubbles are usually small and may not be visible at first, but they gradually grow in size as more gas comes out of the water.

The rate at which the bubbles form and grow depends on several factors, such as the temperature of the water, the pressure, and the amount of dissolved gases present in the water. Warmer water releases dissolved gases faster than cold water, so you may notice the bubbles forming more quickly in warm tap water. Higher atmospheric pressure also promotes the formation of bubbles, as it increases the solubility of gases in water.

The presence of dissolved gases in water is not a cause for concern. These gases are naturally occurring and are not harmful to human health. However, if the water has a high concentration of dissolved gases, it can affect its taste and appearance, and make it less refreshing to drink. In such cases, you can remove the dissolved gases by boiling the water or letting it sit for a longer period so that the bubbles can dissipate.