Answer:
Except the example number three all are obeying the law of conservation of mass.
Explanation:
Definition:
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
Explanation:
This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
For example:
1 = 4 gram of carbon combine with 9 grams of oxygen to produce 13 grams of carbon dioxide.
C + O = CO₂
4 g + 9 g = 13 g
13 g = 13 g
This reaction followed the law of conservation of mass.
2= 20 grams of paper is burned to product 7 grams of ash and 13 grams of smoke and gases
paper = ash +( smoke + gases)
20 g = 7 g + ( 13g)
20 g = 20 g
This reaction followed the law of conservation of mass.
3 = 3 grams of hydrogen react with 2 grams of oxygen to produce 6 grams of water
H + O = H₂O
3 g + 2 g = 6 g
5 g = 6 g
This reaction not followed the law of conservation of mass.
4 = 5 grams of reactants react to form 5 grams of products
reactants = products
5 g = 5 g
This reaction followed the law of conservation of mass.
