A solution of hydrochloric acid had a hydrogen ion concentration of 1.0 mol/dm3 water was added to the hydrchloric acid until the pH increased by 1.
What was the hydrgoen ion concentration of the hydrochloric acid after water had been added?

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

i don,t know so just answer mine

wher is the rest of the question