How many o atoms are in 1.25 mol of so2

The number   of  O atoms  that ate in 1.25  mol   of SO2  is  2.5  moles

  calculation

moles of O= total number O atoms in SO2    x  1.25  moles

The number  of  O  atoms in SO2 =   1  x2 = 2 atoms

moles is therefore=   2  x 1.25 moles = 2.5 moles

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e

the dependant variable is spilled water

the independent is the heat