Aglass break: this a physcal change right?

answer: yes

explanation: a physical change is a type of change in which the form of matter is altered but one substance is not transformed into another. the size or shape of matter may be changed, but no chemical reaction occurs. physical changes are usually reversible. note that whether a process is reversible or not is not truly a criterion for being a physical change.

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