Is carbonic Acid a liquid at room temp?
Carbonic acid is unstable. When you dissolve carbon dioxide in water, a small amount of it reacts to give the carbonic acid molecule (H2CO3). However, you can’t easily isolate this as a pure substance – as the water evaporates, for example, carbon dioxide is given off as well, so that by the time that there’s no water left, there’s no H2CO3 left either – all of it has decomposed to CO2 and H2O. However, it is possible to produce pure carbonic acid by irradiation of solid carbon dioxide and solid water (ice and dry ice), and it seems that it decomposes only very slowly when water is not present. Since it is highly polar, I would predict that it should be liquid at room temperature.
