IDNStudy.com, kung saan ang iyong mga tanong ay may malinaw at konkritong sagot. Magtanong at makatanggap ng eksaktong sagot mula sa aming mga bihasang miyembro ng komunidad.

which of the following is NOT an evidence that a chemical reaction has occurred?
A.change in compostion
B.change in color
C.change in form
D.change in odor

air pollution is produced due to the combustion of fossils fuels. what factor mostly affects combustion?
A.presence of heat and oxygen
B.absence of heat and oxygen
C.change in the amount of air
D.presence of precipitate​