The conservation of mass principle states that in a closed system, the total mass of the reactants must equal the total mass of the products in a chemical reaction. In terms of a chemical equation, this is depicted by ensuring that the number of atoms of each element is the same on both sides of the equation.
For the reaction between iron (Fe) and oxygen (O₂) to form iron oxide (Fe₂O₃), the balanced chemical equation is:
\[ 4 \text{Fe} + 3 \text{O}_2 \rightarrow 2 \text{Fe}_2\text{O}_3 \]
In this equation:
- Reactants: 4 iron atoms and 6 oxygen atoms (from 3 O₂ molecules).
- Products: 4 iron atoms and 6 oxygen atoms (from 2 Fe₂O₃ molecules).
When you count the atoms:
-
On the left side (reactants), you have:
- 4 Fe atoms
- 6 O atoms (3 O₂)
-
On the right side (products), you have:
- 4 Fe atoms (from 2 Fe₂O₃)
- 6 O atoms (from 2 Fe₂O₃)
Since the number of each type of atom is the same on both sides of the equation, it shows that mass is conserved during the reaction. No atoms are lost or gained; they are simply rearranged to form new substances. Thus, the chemical equation represents the conservation of mass, confirming that all matter is accounted for before and after the reaction.
1 answer