A scientist describes the molecules of a substance as it changes from one state of matter to another. She states that the speed of the molecules slows down over time. Which phase change could the scientist be describing? A. gas to liquid
B. liquid to gas
C. solid to gas
D. solid to liquid

A.

Explanation:

Particles in gas move very fast and quickly while particles in liquids are slow and closer together.

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.

frequency, z, and the collision density, z, in carbon dioxide (co2), r 180 pm at 30 °c and 120 kpa