What is meant by the law of conservation of mass? If 12 g of C is burnt in the presence of O2, how much CO2 will be formed?
[Atomic mass of C = 12 u, O = 16 u]
Law of conservation of mass: This law states that “atoms are neither created nor destroyed in a chemical reaction”.
This means that the total mass of the products formed in chemical reaction must be equal to the mass of reactants consumed.
Carbon + oxygen → CO2
Mass of carbon = 12g
Mass of oxygen = 32g
Mass of CO2 =?
According to the law of conservation of mass,
Sum of masses of reactants = Sum of masses of of products
Hence, 12g + 32g = 44g
Thus, the amount of CO2 formed is 44g.