To be successful with this question, you need to know what a balanced chemical equation involves. You also need to have a good strategy for how to balance a chemical equation. Finally, you will need to make sure you know how to conduct an Atom Count. The two infographics below describe these three ideas. Study the graphics, giving particular attention to the
Know How to Count Atoms, the
Step-by-Step Balancing Method, and the
Example sections in the second infographic. Some specific information regarding this question are provided after the second infographic.
Some Specifics About This Question Group
The two versions of questions in this Question Group have a very similar skeleton equation. It's just that one of the equations contains Zn and the other Cu. There are two reactants and two products in each. For both versions, the elements H and O shows up in both formulae on the product side. As such, do not begin the balancing act by balancing H or O. Instead, begin with the element Zn (or Cu). Once the Zn (or Cu) is balanced, make an effort to balance the element P. Once you have balanced the Zn (or Cu) and the P elements, you will notice that all the H-containing formulae have coefficients in front of them with the exception of the product H
2O. So your third element to balance would be H; place a coefficient in front of H
2O to balance H. Conduct an atom count (enter numbers of atoms of each element into the Atom Panel). Check to insure that the element O is balanced. If it is, then you're done. As is often the case, following the step-by-step method usually provides an auto-balancing of the last element.