Figure 1-77. Order of reactivity of selected metals toward acids. In Figure 1-77, the metals on the right from hydrogen (symbols in black) do not displace hydrogen from acids. The ones on the left (symbols in red) do, their reactivity increasing from right to left. We will learn why soon. Meanwhile, just remember that the ability of different metals to react with acids can be very different. For example, while tin (Sn) reacts with concentrated HCl only sluggishly, the
reaction of zinc (Zn) is quite vigorous,
sodium (Na) reacts violently, and
potassium (K) even more so. The reaction of HCl with K is particularly spectacular (and dangerous)!
Another thing to keep in mind is that when it comes to reactions of acids with metals, nitric acid (HNO
3) is exceptional. Nitric acid reacts even with some of those metals that do not react with other acids, the ones to the right from the hydrogen in Figure 1-77. These reactions, however, are of a different type. Only on a rare occasion do they produce H
2. We will study reactions of nitric acid with various metals in considerable detail in Volume 3 of this course.
(4). Acids can react with some salts to give hydro salts (Figure 1-78).