An atom of calcium has 2 valence electrons and an atom of sulfur has 6 valence electrons. how many lone pairs of electrons are present in the lewis structure of calcium sulfide? one two three four none

Different isotopes indicate that an element will have different numbers of

How many atoms of mg are present in 97.22 grams of mg? 6.022 × 1023 2.408 × 1024 4.818 × 1024 5.855 × 1025

Ted and emily played a mixed doubles tennis match against jack and brenda. in the second match. ted and brenda played against jack and emily. which type of chemical reaction does the situation demonstrate?