Which is not a true statement about the evidence to support the origin of our universe? A. Galaxies are expanding at an exponential rate in the universe
B. The universe is continually heating up and gaining energy
C. Leftover light from the oldest light in the universe is observable
D. Hydrogen makes up about 73%, and helium makes up about 25% of all the mass in the universe

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

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