Using a periodic table, answer the following question: Which series of elements have the same number of valence electrons?
A. Sn, Pb, F, I
B. Ca, Sr, Cu, Ag
C. Na, Mg, Si, B
D. N, P, Sb, Bi

Count the number of each type of atom in the equation below, and then balance the equation. write in the numbers of atoms and coefficients. add a 1 if there should be no coefficient. cs2(l) + o2(g) → co2(g) + so2(g) c [ ] s [ ] o > c [ ] s [ ] o [ ] cs2(l) + [ ] o2(g) > [ ] co2(g) + [ ] so2(g)