Lime water turns milky when it is exposed to carbon dioxide and sulfur dioxide. A simple experiment that can be done to demonstrate this is to take some lime water and drop some pieces of burning match or lighted candle in it.
The flame of these objects are a combination of oxygen and carbon dioxide, which reacts with the calcium hydroxide in the lime water (also known as slaked lime) creating calcium carbonate, resulting in the lime water turning milky.
Sulfur dioxide, which is present in the atmosphere, is an additional gas that can cause lime water to react and turn milky.
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What turns Limewater milky other than co2?
Limewater turning milky has nothing to do with CO2, but is actually due to the presence of calcium hydroxide in it. Calcium hydroxide, or slaked lime, is an ionic compound that is formed when calcium oxide (also known as lime or quicklime) is mixed with water.
In solutions with hydroxide ions present, two reactions are at work; one is the precipitation of hydrated calcium carbonate and the other is the hydrolysis of the bicarbonate ions. The precipitation of hydrated calcium carbonate is what causes the milky appearance of limewater.
This compound is also known as milk of lime, as it turns solutions white and opaque. In addition, when slaked lime is mixed with water, it also produces a significant amount of heat, making it an exothermic reaction.
Why does lime water turn milky with carbon dioxide?
Lime water turns milky when carbon dioxide is added because the acid in the lime water (calcium hydroxide) reacts with the carbon dioxide to produce calcium carbonate. This calcium carbonate is a white, solid, precipitate that causes the lime water to turn cloudy or milky.
If a small amount of carbon dioxide is added to the lime water, the solution will become turbid. If a large amount of carbon dioxide is added to the lime water, the solution will become a solid mass of calcium carbonate.
This change in the appearance of lime water when carbon dioxide is added is an example of a chemical reaction or a precipitation reaction. Lime water is used as an indicator for carbon dioxide gas. When observing a clear, odorless gas, it may be hard to tell if it is composed of carbon dioxide or not.
However, when the gas is passed through lime water, if it is carbon dioxide, the lime water turns milky. This physical change of the lime water is a reliable indicator of the presence of carbon dioxide.
What happens when CO2 is added to lime water?
When CO2 is added to lime water, a chemical reaction takes place. The carbon dioxide reacts with the calcium hydroxide, a base, in the lime water to form calcium carbonate, a precipitate. This process is known as carbonation and results in the production of bubbly or fizzy water.
The gas released during this reaction is released as tiny bubbles and is what gives beverages like soda their fizziness. This reaction is also used to create a doser of carbonated water at home. In addition to the formation of the white precipitate, the reaction also reduces the alkalinity and raises the acidity of the solution slightly.
This is why adding CO2 to lime water can make it more palatable, as it lowers the pH somewhat.
Why does CO2 turn lime water milky but if passed for a long time the solution becomes clear again?
The addition of CO2 to lime water causes a chemical reaction that occurs when the insoluble calcium carbonate in the lime water reacts with the gaseous carbon dioxide. This reaction results in the formation of tiny, insoluble particles of calcium carbonate suspended in the solution, creating a cloudy or “milky” appearance.
Over time, these particles settle out of the solution and the water eventually becomes clear again. The settling occurs because the calcium carbonate particles are relatively heavy and they eventually fall out of the water at the bottom of the container, leaving the top water clear again.
When co2 is passed through lime water turns milky on passing excess co2 the solution becomes Colourless due to the formation of?
When carbon dioxide (CO2) is passed through lime water, it turns the mixture milky due to the formation of calcium carbonate (CaCO3). When an excessive amount of CO2 is passed through the lime water, the solution will become colourless due to the complete saturation of the carbon dioxide and the reaction coming to an end.
This occurs because of the reaction between the CaCO3 and CO2: CaCO3(s) + CO2(g) —-> CaCO4(s) + H2O(l). The calcium carbonate can no longer react with the CO2 in excess, so the water remains colourless.
What happens when co2 is passed through Limewater from short time and long time?
When carbon dioxide is passed through limewater, the limewater initially appears to remain unchanged in the short term; however, over time it will start to take on different properties. In the short term, when carbon dioxide is passed through the limewater, the carbon dioxide gas reacts with the water molecules in the limewater to form carbonic acid.
This acid lowers the pH of the limewater over time, turning it into a milky white color as calcium carbonate is dissolved in the water. As more carbon dioxide is passed through the limewater over a longer period of time, it will eventually be fully saturated with carbon dioxide and turn into carbonic acid.
This causes the limewater to become even more acidic, eventually dropping its pH level to nearly 2. This makes it an extremely strong acid, which can be damaging to skin and other surfaces. Additionally, continued long-term exposure to the highly acidic limewater can lead to the calcium carbonate forming more solid particles, resulting in White deposition.
