Across
- 4. A characteristic of a pure substance that can be observed without changing it into another substance
- 5. A reaction that release energy, usually in the form of heat
- 8. Two or more substances that are together in the same place but their atoms are not chemically bonded
- 9. A mixture that contains as much dissolved solute as is possible at a given temperature
- 12. A mixture in which particles can be seen and easily separated by settling or filtration
- 15. A reaction that absorbs energy
- 17. The basic particle from which all elements are made; the smallest particle of an element that has that properties of that element
- 18. A short, easy way to show a chemical reaction, using symbols
- 20. A tiny, negatively charged particle that moves around the outside of the nucleus of an atom
- 21. A small particle in the nucleus of the atom, with no electrical charge
- 22. An atom or group of atoms that has become electrically charged
- 23. The average mass of all the isotopes of an element
- 25. The attraction between oppositely charges ions
Down
- 1. The electrons that are in the highest energy level of an atom and that are involved in chemical bonding
- 2. A region of an atom in which electrons of the same energy are likely to be found
- 3. A reaction in which one element replaces another in a compound or when two elements in different compounds trade places
- 6. A material that decreases the rate of a reaction
- 7. The minimum amount of energy needed to start a chemical reaction
- 10. A substance that cannot be broken down into any other substances by chemical or physical means
- 11. A chemical reaction in which two or more simple substances combine to form a new, more complex substance
- 13. Small, positively charged particles that are found in the nucleus of an atom
- 14. The amount of space that matter occupies
- 16. A mixture that has a lot of solute dissolved in it
- 19. A compound that consists of positive and negative ions
- 24. The amount of matter in an object