Determine from the balanced chemical reaction if the derived mole ratio is correct or incorrect.

4Zn + 10HNO3 yields 4Zn(NO3)2 + N2O + 5H2O

(4 moles Zn / 5 moles H2O)

Iknow the answer to 13 is b and 14 is d. i just need to know why the correct answers are correct

1) in saturated limewater, [h+ ]=3.98x10-13 m. a) find [oh]-/ b) what is the ph? / c) is the solution acidic, basic, or neutral? / 2) in butter, [h+ ]=6.0x10-7 m. a) find [oh]-/ b) what is the ph? / c) is the solution acidic, basic, or neutral? / 3) in peaches, [oh]=3.16x10-11 m a) find [h+ ]/ b) what is the ph? / c) is the solution acidic, basic, or neutral? / 4) during the course of the day, human saliva varies between being acidic and basic. if [oh]=3.16x10-8 m, a) find [h+ ]/ b) what is the ph? / c) is the solution acidic, basic, or neutral? /

The excretory system, need answers for all: )