Hydrogen peroxide is sold as a 3.0% (by mass) solution. the rest of the solution is water . how many grams of hydrogen peroxide are in 250 grams of this solution?

Astable electron arrangement for an atom is one that does not easily change. how is this arrangement arrived at? a. valence electrons are transferred or shared to create a full outer shell of electrons. b. valence electrons are discarded into space to create a full outer shell of electrons. c. protons (positive charge) pair with valence electrons (negative charge) to create a strong bond. d. outer shells with valence electrons are transferred or shared.

What is calcium oxide+diphosphorus pentoxide--> calcium phosphate balanced

At which temperature would a reaction with ah= -220 kj/mol and as=-0.05 kj/(mol-k) be spontaneous?