Chemistry worksheet focusing on Chapter 12 concepts, including definitions and matching terms related to chemical reactions and solutions.

Here's the correct matching for each numbered definition with the corresponding lettered term from the word bank:

---

1. any substance that occupies space
→ B. matter
*(Matter is anything that has mass and occupies space.)*

2. is the smallest form of chemical matter
→ S. element
*(An element is a pure substance made of only one type of atom — the simplest form of matter that cannot be broken down chemically.)*

3. is the rapid oxidation of a substance accompanied by the production of heat and light
→ K. combustion
*(Combustion is a rapid exothermic reaction involving oxygen, often producing flames, heat, and light.)*

4. is a substance that releases oxygen
→ E. oxidizing agent
*(An oxidizing agent accepts electrons and often provides oxygen in reactions.)*

5. is a substance that adds hydrogen to a chemical compound or subtracts oxygen from the compound
→ I. reducing agent
*(A reducing agent donates electrons, often adding H or removing O.)*

6. oxidation-reduction is also known as
→ A. redox
*(Short for reduction-oxidation.)*

7. is a stable physical mixture of two or more substances in a solvent
→ U. solution
*(A homogeneous mixture where one substance (solute) is dissolved in another (solvent).)*

8. is the substance that is dissolved into solution
→ M. solute
*(The component that dissolves in the solvent.)*

9. is the substance that dissolves the solute and makes the solution
→ V. solvent
*(The medium in which the solute dissolves.)*

10. liquids that are not capable of being mixed together to form a stable solution
→ R. immiscible
*(Immiscible liquids do not mix — e.g., oil and water.)*

11. unstable physical mixtures of undissolved particles in a liquid
→ N. suspensions
*(Suspensions contain larger particles that settle out over time.)*

12. is an unstable physical mixture of two or more immiscible substances
→ C. emulsion
*(Emulsions are temporary mixtures of immiscible liquids, like oil and vinegar before separating.)*

13. substances that allow oil and water to mix, or emulsify
→ O. surfactants
*(Surfactants reduce surface tension and stabilize emulsions.)*

14. The tail of the surfactant molecule is called ______
→ D. lipophilic
*(Lipophilic = “fat-loving” — the nonpolar tail that interacts with oils/fats.)*

15. The head of the surfactant molecule is called ______
→ W. hydrophilic
*(Hydrophilic = “water-loving” — the polar head that interacts with water.)*

16. is a colorless gas with a pungent odor
→ G. ammonia
*(Ammonia (NH₃) is a colorless gas with a sharp, irritating smell.)*

17. is a sweet, colorless, oily substance. It is used as a solvent and as a moisturizer in skin and body creams.
→ L. glycerin
*(Glycerin (glycerol) is a viscous, sweet-tasting liquid used in cosmetics and pharmaceuticals.)*

18. measures the acidity and alkalinity of a substance
→ J. pH scale
*(The pH scale ranges from 0–14 and indicates how acidic or basic a solution is.)*

19. commonly known as lye
→ T. sodium hydroxide
*(Sodium hydroxide (NaOH) is a strong base, commonly called lye.)*

20. an ion with a negative electrical charge is an ______.
→ P. anion
*(Anions are negatively charged ions, formed when atoms gain electrons.)*

21. mean multiples of 10 on the pH scale
→ F. logarithm
*(The pH scale is logarithmic — each unit change represents a 10-fold change in H⁺ concentration.)*

22. oil droplets are emulsified in water
→ H. oil-in-water emulsion
*(Example: milk — oil droplets dispersed in water.)*

23. water droplets are emulsified in oil
→ Q. water-in-oil emulsion
*(Example: butter — water droplets dispersed in oil.)*

---

✔ Final Answer Key:

1. B
2. S
3. K
4. E
5. I
6. A
7. U
8. M
9. V
10. R
11. N
12. C
13. O
14. D
15. W
16. G
17. L
18. J
19. T
20. P
21. F
22. H
23. Q

Let me know if you’d like this formatted as a worksheet answer key!