1. 2Pb(NO₃)₂ → 2PbO + 4NO₂ + O₂
2. CH₄ + 2O₂ → CO₂ + 2H₂O
3. Cu + 2AgNO₃ → Cu(NO₃)₂ + 2Ag
4. MnO₂ + 4HCl → MnCl₂ + 2H₂O + Cl₂
5. Pb(NO₃)₂ + 2NaCl → PbCl₂ + 2NaNO₃
1)

2)
CuSO_4+Cu_2Cl_2\neq>

H2O is the missing reactant.
Just a caveat: this equation isn’t balanced.
Answer: 1.005919176541433
Explanation:
Answer:
D. The higher energy chair conformation contains two axial methyl groups.
Explanation:
The diaxial trans-1,4-dimethylcyclohexane has the highest energy (the least stable) and the diequatorial chair conformation has the lowest energy (the most stable).
The diaxial conformation has a higher energy due to the interaction between the methyl groups.