A18.0 -\,l volume of an ideal gas in a cylinder with a piston is at a pressure of 3.2 atm. enough weight is suddenly removed from the piston to lower the external pressure to 1.6 atm. the gas then expands at constant temperature until its pressure is 1.6 atm.
1. find delta e for this change in state in j
2. find delta h for this change in state in j
3. find q for this change in state in j
4. find w for this change in state in j

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

when [oh-] is 10-5  m, and [h3o+] is 10-9  m, the poh is 5 and ph is 9. again in both cases the sum of ph and poh is 14. however, the hydrogen ion concentration is not always going to be equal to exactly 1 x 10 raised to a negative number. for example, we skipped over the value of 2.0 x 10-7.

um i think it might be a car?

1 is the answer to this problem