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Tricks and tips for everyone

# How does the candle water trick work?

## How does the candle water trick work?

Once the glass is standing on the plate, the burning candle uses up all the available oxygen in the glass, then goes out. As it does so, the air in the glass cools, and as it cools, the air pressure in the glass falls below atmospheric pressure. Water is drawn into the glass until the pressure is equalised.

## What is the purpose of the candle burning experiment?

The experiment teaches of role of oxygen in fire and its presence in the air. This one takes less than 5 minutes to complete it. Kids who are less than 5 can only understand that oxygen is required for a candle to burn and when we close with the glass tumbler oxygen goes off and hence the candle.

What happens when you put a glass over a candle in water?

What happens if you cover a lit candle in a water basin with a glass? The glass becomes foggy on the inside and the flame fades and eventually goes out. Then the water level in the glass rises. The burning candle produces carbon dioxide and water in the form of water vapor.

What caused the water to rise in the glass?

Water vapor condenses to moisture on the glass, causing lower air pressure. Outside air pressure does not change. To reach equilibrium, the area must decrease, so the water rises into the glass.

### What effect does the size of the candle have on how high the water rises?

The height to which the water rises varies with candle thickness because thicker candles have a larger volume. The difference will be more noticeable in bottles with a narrow neck than wide mouth jars and if the diameter of the thicker candle is close to the inner diameter of the neck of the bottle.

### Why do you think food coloring is added to the water in rising water experiment?

Step 2: If you want, add food coloring to the water. This just makes it easier to see and is fun, so totally optional. Step 3: Place your small votive in the middle of the dish. Step 4: Light the candle, then quickly place the empty glass over the flame, touching the water.

What gas law is the candle and water experiment?

When the candle burns out (because all the oxygen is used up), the temperature cools quickly. This temperature decrease means the volume also decreases, which lets the water rise to fill up that space. This is called Charles’s Law.

What law is the candle experiment?

Charles’s Law
The candle warms the air, and this increases the air volume inside the glass. When the candle burns out (because all the oxygen is used up), the temperature cools quickly. This temperature decrease means the volume also decreases, which lets the water rise to fill up that space. This is called Charles’s Law.

## What is the actual explanation for why the water rose up into the flask?

The cooling, contracting air creates a vacuum (a lower pressure) in the flask. Lower pressure inside and higher pressure outside means the water is pushed up into the flask until the air pressure inside is equal to the air pressure outside the flask.

## What is the gas law that explains the rising of water in a glass?

This temperature decrease means the volume also decreases, which lets the water rise to fill up that space. This is called Charles’s Law. Charles’s Law tells us that the ratio of volume to temperature must remain the same, so if one goes down the other goes down too.

What gas law is candle and water experiment?

Why the level of water in the tube falls first and then starts to rise when the flask is heated?

It falls because the glass in the flask starts to expand before the water inside. When the heat energy reaches the water it expands. So the expansion of liquid you see in a thermometer is really the expansion of liquid less the expansion of the glass tube.