Final answer:
After analyzing the provided chemical equations, it is clear that the first equation needs to be corrected and properly balanced to respect the conservation of mass. For the second and third equations, they are indeed balanced with equal numbers of each type of atom on both sides of the equation.
Step-by-step explanation:
Chemical Equations Balance Check
The question involves checking if chemical equations are balanced. A balanced equation has the same number of each type of atom on both sides of the arrow. Using this principle, we analyze the given equations:
- 2Hg(e) + O2(g) → Hg2O2 (s) is incorrect and should be corrected to 2 Hg (l) + O2(g) → Hg2O2 (s). Elements are represented with their chemical symbols, e.g., Hg for mercury and O for oxygen. This equation is not balanced because the oxygen on the left side of the equation is diatomic (O₂) but only shows up as a single atom of oxygen in the product (Hg₂O₂).
- C₂H₄(g) + 2O₂(g) → 2CO₂(g) + 2H₂O(l) is balanced, representing a complete combustion of ethylene (C₂H₄) in oxygen to yield carbon dioxide and water.
- Mg(NO₃)₂(s) + 2Li(s) → Mg(s) + 2LiNO₃(s) is balanced, showing the reaction of magnesium nitrate with lithium metal to produce magnesium metal and lithium nitrate.
It is important to ensure that the number of atoms of each element is conserved from reactants to products to satisfy the Law of Conservation of Mass.