Consider the equation CH4 + O2 —> 2H2O + CO2 Which element or elements are unbalanced in this equation?

C, H and O are all unbalanced

Both H and O are unbalanced

Only the H is unbalanced

Only the O is unbalanced

With the largest atoms and the smallest number of valence electrons and with the smallest atoms and the greatest number of valence electrons are the most reactive. a. nonmetals; metals b. nonmetals; transition elements c. transition elements; metals d. metals; nonmetals