Aquantity of energy equal to 8.90 × 1012 joules was emitted from a nuclear reaction. what amount of mass was required to be converted to yield this amount of energy? 9.90 × 10-5 kg 2.96 × 10-4 kg 2.67 × 104 kg 8.01 × 105 kg

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