How many valence electrons does an atom of this element have : 2e-8e-8e2e?

Imagine that you have produced several versions of lactase, each of which differs from normal lactase by a single amino acid. describe a test that could indirectly determine which of the versions significantly alters the three-dimensional shape of the lactase protein.

The name of the ion, s2-, is: sulfurous ion sulfide ion sulfur ion sulfate ion

How does the principle of electromagnetism explain the interaction between earth’s magnetic field and the solar wind?