Are changes in the state of matter (phase) considered physical or chemical changes? Why?

Check the correct box to describe the periodic trends in electronegativity. electronegativity across a period: decreases. increases. electronegativity down a group: decreases. increases.

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? /

Which statement correctly identifies the scientific question and describes why the question is scientific? question 1 refers to the supernatural. question 2 reflects a moral or social value. question 3 refers to something that can be measured. question 4 reflects a question that can’t be observed.