<em>1. Write out all the ions/elements and indicate whether they are reactants or products. </em>
<u>Reactants:</u>
Aqueous Hydrochloric Acid: HCl (H has a charge of +1 and Cl has a charge of 1-, so when an ionic bond forms they will form HCl).
Solid Zinc: Zn (since it is a solid zinc with no other forms of elements, the zinc is pure).
<u>Products:</u>
Hydrogen gas: H2 (it has to be H2 because Hydrogen is a diatomic element, and when by itself during reactions, will be H2 instead of H).
Aqueous Zinc Chloride: ZnCl2 (Zn has a charge of 2+ and Cl has a charge of 1-, so through an ionic bond, they will form ZnCl2).
<em>2. Using this information, you can then write out the unbalanced equation.</em>
HCl + Zn -> H2 + ZnCl2
<em>3. Next, indicate their states of matter and any aqueous solutions. </em>
HCl (aq) + Zn (s) -> H2 (g) + ZnCl2 (aq)
<em>4. Try different numbers until you get the same numbers of H, Cl, and Zn on both sides. </em>
2 HCl (aq) + Zn (s) -> H2 (g) + ZnCl2 (aq)
As you can see, the equation contains 2 Hydrogen atoms on both sides, 2 Chloride atoms on both sides, and 1 Zinc atom on both sides. The equation is chemically balanced.
