Carbondiooxide does not support in burning but mg burs in it why.?

To keep burning, fires require oxygen. Carbon dioxide is used in certain fire extinguishers to put out flames. Explanation: Because magnesium is higher on the reactivity scale than carbon, it is more reactive and eliminates oxygen from carbon dioxide (to give carbon and magnesium oxide).

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of c is as shown here in the image.