"Put lithium powder into copper sulfate solution at room temperature, 2Li+Cu2+ = Cu+2Li+" Why? ...

You are wrong. According to the diagonal principle, lithium and magnesium have similar metallic properties and can indeed react. At this time, you should pay attention. Can't Na also react with non-oxidizing acids? Then why didn't he react with water first?

In fact, it can be explained that this is because the atomic (ionic) radius of lithium and beryllium is particularly small.

For example, the high charge densities of Li+ and Be2+ make them extremely polarized, and the valence of their compounds even exceeds ionic.

The valence of LiI is about 50%;

The valence of BeI2 is about 75%.

Because the electrode potential is the size of the metal's ability to lose electrons in solution, and? H correlation. And I'm just writing? Part h:? H=S+I+？ Double hardness

Because the hydration energy (negative value) of plum is particularly large, although the ionization energy and sublimation energy of plum are larger than that, but its? H is smaller than Na.