Water. Glucose { C }_{ 6 }{ H }_{ 12 }{ O }_{ 6 } and Oxygen { O }_{ 2 } gets in, Carbon dioxide { CO }_{ 2 } and water { H }_{ 2 }O comes out from the reaction.
{ C }_{ 6 }{ H }_{ 12 }{ O }_{ 6 }(s)+6{ O }_{ 2 }(g)\rightarrow 6C{ O }_{ 2 }(g)+6{ H }_{ 2 }O(l)+heat is the exact reaction.
