If 12 g of carbon combines with 32 g of oxygen, the carbon dioxide formed is:

1. No mass is lost or gained in the reaction. 2. So the product weighs as much as the reactants together. 3. 12 g plus 32 g gives 44 g of carbon dioxide. 4. So the answer is 44 g. _Source: NCERT Class 9 Science, Ch 9 'Atomic Foundations of Matter'_