At room temperature carbon is a solid gas or solid and when it gets to a high enough temperature to melt then the carbon becomes a liquid.
Carbon has a very high melting point and stays a solid even at temperatures much higher than the highest melting-point metals such as tungsten or rhenium.
At normal atmospheric pressure, carbon does not melt when heated but instead it sublimes. i.e. it undergoes a phase change directly from solid to gas. If the pressure is increased to 10 atmospheres carbon (graphite) is observed to melt at 6,422 F.
So at room temperature the carbon would remain a solid gas and not become liquid until it reached a very high temperature which no home or place could get too.
You would have to heat the carbon up in a very hot oven or something to get it hot enough to turn it into a liquid.