Chemical substance

High school (ages 12+)
Science & Technology

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/chemical-substance

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the defining criterion?Invariant chemical composition and characteristic properties
2. What is the physical states?Can exist as solid, liquid, gas, or plasma without altering chemical identity
3. Why does water always boil at 100°C?Because the atoms in pure water are arranged the same everywhere, so the temperature at which it turns to vapor is always 100°C at normal pressure.
4. How can a substance change from solid to liquid?When heat is added, the particles move faster and the substance melts, but the chemical identity stays the same.

Chemical Identity: The fundamental nature of a substance determined by its atomic or molecular composition.
Phase Transition: The physical process of changing between states of matter (solid, liquid, gas, plasma).
Inert Substance: A chemical substance that does not readily undergo chemical reactions.