The volume of a sample of gas, initially at 25 °C and 158 mL, increases to

450.mL. What is the final temperature of the sample of gas, if the pressure

in the container is kept constant?

The final temperature = 848.7 K or 575.7 °C

Explanation:

Step 1: Data given

Temperature = 25.0 °C = 298 K

Volume = 158 mL = 0.158 L

The volume increases to 450 mL = 0.450 L

The pressure is constant

Step 2: Calculate the final temperature

V1/T1 = V2/T2

⇒with V1 = the initial volume = 0.158 L

⇒with T1 = the initial temperature = 298 K

⇒with V2 = the increased volume = 0.450 L

⇒with T2 = the new temperature = TO BE DETERMINED

0.158 L / 298 K = 0.450 L / T2

T2 = 0.450 L / (0.158L/298K)

T2 = 848.7 T

The final temperature = 848.7 K or 575.7 °C

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.