The answer is; D
Enthalpy is the system’s internal energy ( considering the product of its pressure and volume). When the enthalpy is negative, it means that the products have a lower energy level than the reactants - meaning the system has dispensed some energy into the environment.
Answer:
2Zn + PbCl4 → 2ZnCl2 + Pb
N.B: ZnCl2 is zinc chloride
Pb is lead
Explanation:
Zinc has a chemical symbol Zn while lead(IV) chloride has the chemical formula, PbCl4. Combining these two substances in a reaction will give rise to the following:
Zn + PbCl4 → ZnCl2 + Pb
However, this equation is not balanced. To balance the equation, we make sure that the atoms of each element on both sides of the reaction are equal. This is done as follows;
2Zn + PbCl4 → 2ZnCl2 + Pb
N.B: ZnCl2 is zinc chloride
Pb is lead
Isotopes of atoms d. have the same number of protons but a different number of neutrons.