At 303 K, the volume of a gas is 30.0 ml. At constant pressure, what is the new volume of the gas if the temperature is decreased to 283K?

V₂ = 28 mL

Explanation:

Given data:

Initial temperature = 303 K

Initial volume = 30.0 mL

Final temperature = 283 K

Final volume = ?

Solution:

The given problem will be solve through the Charles Law.

According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.

Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume  

T₂ = Final temperature

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

V₂ = V₁T₂/T₁  

V₂ = 30.0 mL × 283 K /303 K

V₂ = 8490 mL.K / 303 K

V₂ = 28 mL

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