A reaction occurs when we add butane liquid to a coke then we flip the bottle upside down. As seen in the video experiment, the coke bottle flew like a rocket. Butane is a flammable gas and is in liquid form if it is below 0 degree Celsius. The boiling point for a butane liquid is 0 degree Celsius which means that anything warmer than 0 degree Celsius will convert the liquid into gas.
When the butane liquid was sprayed on top of the Coke solution, they do not mix together and that is because butane liquid has a property of being non-soluble and has lighter weight than the Coke solution. By the time the butane liquid is out of the container, it is already being transformed into gas at a slow rate. Upon flipping the bottle upside down, butane's gas moves upward and the Coke solution flows downward forcing itself to the butane liquid and gas. A coke has a solution that causes a warm reaction to the butane liquid thus causing it to be converted to a gas at a faster rate. Since more gas are being released and are moving upward at a faster rate, they are trapped in the coke bottle because there is no hole where to escape upwards causing them to be compressed in the bottle until it gets full of gas thus building up pressure. Since there is a hole below the flipped bottle container, all pressure moves toward that direction producing enough force to push the coke bottle upwards with the help from the ground. If the hole where to escape is too small and the production of gas from the butane liquid is much faster than expected, there are chances that the Coke bottle cannot hold the contained pressure anymore and explodes instead.