The ionic equations represent the reactions between four metals, p, q, r and s, and solutions of the salts of the same metals

p + q2+ -> no reaction
r + p2+ -> r2+ + p
q + s2+ -> q2+ + s
s + p2+ -> s2+ + p
s + r2+ -> s2+ + r
s + q2+ -> no reaction

what is the correct order of reactivity of the metals?

most > least
a. p r s q
b. q r s p
c. q s r p
d. s q p r

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.