Abstract: A portable lightweight gas generation device which can be attached to a container to generate a quantity of gas from a mixture of two chemically reactive materials and to inject the gas into the container. The device is especially useful as an apparatus for rapidly carbonating liquid beverages with chemically generated carbon dioxide produced in a gas generation chamber located inside a pressure vessel attached to a liquid container which serves as a carbonation chamber containing the liquid to be carbonated. The generated carbon dioxide is passed from the gas generation chamber to the carbonation chamber to carbonate the liquid. This device can also be used as a means of injecting pressurized gas into a pressurized spray can for dispensing liquids such as paint, hair spray or other sprayable products.