Is Cu2S covalent or ionic

Which of the following would be an accurate picture of the earth during the summer time of the northern hemisphere?

What happens when an atom of sulfur combines with two atoms of chlorine to produce sci2? a. each chlorine atom shares a pair of electrons with the sulfur atom. b. an electron is transferred from each chlorine atom to the sulfur atom. c. an electron is transferred from the sulfur atom to each chlorine atom. d. each chlorine atom shares all its valence electrons with the sulfur atom.

Phosphoric acid is a triprotic acid ( =6.9×10−3 , =6.2×10−8 , and =4.8×10−13 ). to find the ph of a buffer composed of h2po−4(aq) and hpo2−4(aq) , which p value should be used in the henderson–hasselbalch equation? p k a1 = 2.16 p k a2 = 7.21 p k a3 = 12.32 calculate the ph of a buffer solution obtained by dissolving 18.0 18.0 g of kh2po4(s) kh 2 po 4 ( s ) and 33.0 33.0 g of na2hpo4(s) na 2 hpo 4 ( s ) in water and then diluting to 1.00 l.