For the stepwise dissociation of aqueous H3PO4, which of the following is not a conjugate acid–base pair?

A. H2PO4– and HPO42–
B. H3PO4 and H2PO4–
C. HPO42– and PO43–
D. H2PO4– and PO43–
E. H3O+ and H2O

a electronegativity decreases beacuse the size of nucleus is bigger.

a. the law of proportion states the combination of 2 atoms in a specific ratio to produce multiple compounds such as the given statement of question ‘1st compound contains 88.8 % cu ’ indicates 88.8 g of cu is present along with 11.2 g oxygen in 100 g of compound whereas the statement ‘2st compound contains 79.9 % cu ’ indicates 79.9 g of cu is present along with 20.1 g oxygen in 100 g of compound

1st compound contains 88.8 g cu

for cu

m = 63 g /mol

atomic % = 88.8 /63 = 1.42

for o

m = 16 g /mol

atomic % = 11.2 /16 = 0.7

b. the emperical formula of 1st compound is

cu1.4o0.7

cu2o

the objects have the same charge is correct.

nathan lee