Answer: C_6 H_12 O_6
Explanation: The molar mass of glucose is given as 180.16 gm/mol.
It is 40% carbon, so the weight of the carbon is 40% of 180.16 =72.06 gm. The molar weight of the carbon is 12.011 gm, so the total number of the moles of carbon are 72.06/12.011 = 6 moles.
It is 6.719% of hydrogen, so the weight of the hydrogen is 6.719% of 180.16 = 12.105 gm. The molar weight of the hydrogen is 1.008 gm, so the total number of the moles of hydrogen are 12.105/1.008 = 12 moles.
It is 53.27% of oxygen, so the weight of the oxygen is 53.27% of 180.16 = 95.97 gm. The molar weight of the oxygen is 16 gm, so the total number of the moles of oxygen are 95.97/16 = 6 moles.