How do you delay the fizzing in Mentos and Diet Coke?

Cooling it down: Keeping the bottle of Diet Coke and Mentos cold will slow down the chemical reaction and delay the eruption of the fizzing. This can be done by refrigerating the bottle or by adding ice cubes.

Adding other liquids: Adding other liquids, such as water or a different soda, can dilute the Diet Coke and reduce the amount of carbon dioxide gas that is released when the Mentos are added. This will also delay the fizzing.

Using a narrow bottle: The narrower the bottle, the more pressure will build up inside the bottle before the liquid erupts. This can delay the fizzing by several seconds.

Adding oil to the mix: Adding a thin layer of vegetable oil to the surface of the Diet Coke will create a barrier that prevents the carbon dioxide gas from escaping as easily. This will delay the fizzing.

Using different types of Mentos: Different types of Mentos have different surface textures, which can affect how quickly the carbon dioxide gas is released. Some Mentos, such as the mint-flavored variety, have a rougher surface that causes the gas to escape more quickly, while other Mentos, such as the fruit-flavored variety, have a smoother surface that causes the gas to escape more slowly.