A weather balloon contains 9.7 moles of helium at a pressure of 0.955 atm and a temperature of 25 °C at ground level. What is the volume (in L) of the balloon under these conditions?

2.5 × 10² L

Explanation:

Step 1: Given and required data

Step 2: Convert 25 °C to Kelvin

We will use the following expression.

K = °C + 273.15 = 25 + 273.15 = 298 K

Step 3: Calculate the volume (V) of the balloon

We will use the ideal gas equation.

P × V = n × R × T

V = n × R × T / P

V = 9.7 mol × (0.0821 atm.L/mol.K) × 298 K / 0.955 atm = 2.5 × 10² L

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

the answer is a! (2.9 x 10^-18 j) hope i could someone. : )