Tutoring chemistry, ideas about valence electrons are important. The tutor mentions how some atoms have more than 8. Valence electrons are those in the outer shell: electrons involved in bonding or reactions are valence electrons. An early rule chemistry students …

Chemistry: why 3rd row nonmetals can have more than 8 valence electrons Read more »

Self-tutoring about minerals and compounds: the tutor mentions talc. Talc’s formula is Mg3Si4O10(OH)2 and is mined as such. It is used in baby powder, cosmetics, and many other applications. It’s also the main ingredient of soapstone. Source: fda.gov soapstones.com