Vocabulary. Chapter 22: Mixtures

Size: px

Start display at page:

Download "Vocabulary. Chapter 22: Mixtures"

Naomi Allison
5 years ago
Views:

Name: Date: Hour: Vocabulary Chapter 22: Mixtures Read the following passage carefully and use context clues to determine the meaning of the underlined words.

1 Name: Date: Hour: Vocabulary Chapter 22: Mixtures Read the following passage carefully and use context clues to determine the meaning of the underlined words. Italicized words may be unfamiliar as well- use context clues or look them up as needed. Most materials around us are mixtures- mixtures of elements, mixtures of compounds, or mixtures of elements and compounds. Stainless steel, for example, is a mixture of the elements iron, chromium, nickel, and carbon. Our atmosphere is a mixture of the elements nitrogen, oxygen, and argon plus small percentages of carbon dioxide and water vapor. There is a difference between the way substances- elements or compounds- combine to form mixtures, and the way elements combine to form compounds. Substances in mixtures maintain their chemical identity. Tap water is a mixture containing mostly water, but also many other compounds. Leave a pot of boiling water on the stove too long and it evaporates, leaving a chalky mess in the pot. Tap water, even filtered bottled water, is an impure mixture. Since atoms and molecules are so small, it is impossible for a substance to be truly pure. Samples can be purified by various methods, however, when we say pure, it is understood to be a relative term. Sometimes naturally occurring substances are labeled as being pure ( pure orange juice ), but because it contains water, pulp, flavorings, vitamins, and sugars- it is anything but pure! Mixtures may be heterogeneous or homogeneous. For example, orange juice, sand in water, and salad dressing are all heterogeneous mixtures. You can see pulp in orange juice, sand particles in water, or oil in vinegar. On the other hand, homogeneous mixtures do not appear separatedsuch as salt water, blood, milk, etc. A homogeneous mixture may either be a solution or a suspension. A solution is like our atmosphere, we breathe a gaseous solution consisting of the gaseous elements nitrogen and oxygen. Salt water is also a solution because both the water and the dissolved sodium chloride are found in a single liquid phase. In a suspension, the mixing is so thorough that the different phases cannot be readily distinguished. Milk is a suspension because it is a homogeneous mixture of proteins and fats finely dispersed in water. In describing solutions, it is usual to call the component that is present in the largest amount the solvent. The other component is the solute. For example, when a teaspoon of table sugar is mixed with 1 liter of water, the sugar is the solute and the water is the solvent.

2 1. Mixture a. I think the word mixture means: b. Have you heard the word mixture used before? c. The definition of mixture is d. I could use mixture in the following sentence (or example): 2. Impure a. I think the word impure means: b. Have you heard the word impure used before? c. The definition of impure is d. I could use impure in the following sentence (or example): 3. Pure a. I think the word pure means: b. Have you heard the word pure used before? c. The definition of pure is d. I could use pure in the following sentence (or example): 4. Heterogeneous a. I think the word heterogeneous means: b. Have you heard the word heterogeneous used before? c. The definition of heterogeneous is d. I could use heterogeneous in the following sentence (or example):

3 5. Homogeneous a. I think the word homogeneous means: b. Have you heard the word homogeneous used before? c. The definition of homogeneous is d. I could use homogeneous in the following sentence (or example): 6. Solution a. I think the word solution means: b. Have you heard the word solution used before? c. The definition of solution is d. I could use solution in the following sentence (or example): 7. Suspension a. I think the word suspension means: b. Have you heard the word suspension used before? c. The definition of suspension is d. I could use suspension in the following sentence (or example): Words in the reading I didn t know:

4 Chapter 22 Review Questions Read pg in your book Answer the following questions in COMPLETE SENTENCES! 1. Why is drinking water considered a mixture and sodium chloride is not? 2. How can components of a mixture be separate from one another? Explain each. 3. Classify the following as (a) homogeneous mixture, (b) heterogeneous mixture, (c) element, or (d) compound. a. milk d. steel b. ocean water e. blood c. sodium f. planet Earth 4. How is a solution different from a suspension? How can one be distinguished from the other? 5. Why is a ruby gemstone considered to be a solution? 6. What does it mean to say a solution is concentrated? 7. Distinguish between a saturated solution and an unsaturated solution. 8. How is the amount of solute in a solution calculated?

5 9. If you eat metallic sodium or inhale chlorine gas, you stand a strong chance of dying. Let these two elements react with each other, however, and you can safely sprinkle the compound on your popcorn for better taste. What is going on here? (Think about hydrogen gas and oxygen gas forming water) 10. What is the difference between a compound and a mixture? 11. How might you separate sand and salt? How about a mixture of iron and sand? 12. Why is half-frozen fruit punch always sweeter than the same fruit punch completely melted? 13. What is a mole? 14. How much sucrose, in moles, is there in a 2 liter of a 0.5 molar solution? How many moles of sucrose is this? 15. Does 1 liter of a 1-molar solution of sucrose in water contain 1 liter of water, less than 1 liter of water, or more than 1 liter of water?

Chemistry Unit 1: Section1 - Elements, Compounds, & Mixtures

Chemistry Unit 1: Section1 - Elements, Compounds, & Mixtures PURE SUBSTANCES A pure substance is called an element. An element is a pure substance because it cannot be separated into any other substances.