1. A helium-filled balloon had a volume of 8.50 L on the ground at 20.0°C and a pressure of 750.0 Torr. After the balloon was released, it rose to an altitude where the
temperature was 40.0°C and the pressure was .550 atm. What is the new volume of
the balloon in liters at the high altitude?

133.74 L

Explanation:

First we convert the given pressures and temperatures into atm and K, respectively:

Then we use the PV=nRT formula to calculate the number of moles of helium in the balloon, using the data of when it was on the ground:

Then, knowing the value of n, we use PV=nRT once again, this time to calculate V using the data of when the balloon was high up:

im sorry for wasting your time but i have -75 points some how and i think its a glitch

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