What happens to a gas when it is moved from a small container into a big container

Which term best describes the phrase “something that happens”?

Aboxcar traveling at 12 m/s approaches a string of 5 identical boxcars sitting stationary on the track. the moving boxcar collides and links with the stationary cars and they all move off together along the track. what is the final speed of the cars immediately after the collision? (you may take the mass of each boxcar to be 18,537 kg.)

4. a 75.0 g piece of ag metal is heated to and dropped into 50.0 g of water at the final temperature of the mixture is what is the specific heat capacity of silver? 5. a 465 g chunk of iron is removed from petrucci, ralph h.. general chemistry (p. 290). pearson education. kindle edition.