Chapter 6- Lesson 1 Substances and Mixtures

Transcription

1 Chapter 6- Lesson 1 Substances and Mixtures Copy notes on pg 22,24, 26 Pg 198 Vocabulary and Tasty Pizza goes on notebook pg 21 Essential Question for these notes is Describe the difference between atoms, elements, and compounds. 2 charts to copy into pg 23 and 25. Look for the directions on the slides.

2 What is matter? Lesson 1-1 Matter is anything that has mass and takes up space. Anything that does not have mass or volume is not matter.

3 What is matter made of? Lesson 1-2 An atom is a small particle that is the building block of matter. It is the many kinds of atoms and the ways they combine that form the different types of matter.

4 Classifying Matter Lesson 1-3 Scientists place matter into one of two groups substances and mixtures.

5 What is a substance? Lesson 1-4 A substance is matter with a composition that is always the same. A certain substance always contains the same kinds of atoms in the same combination.

6 What is a substance? (cont.) Lesson 1-4 An element is a substance made of only one kind of atom. For example, the element gold is made of only gold atoms, and all gold atoms are alike. Sodium chloride (salt) is also a substance.

7 Lesson 1-4 Element symbols have either one or two letters. Temporary symbols have three letters.

8 What is a substance? (cont.) Lesson 1-4 A molecule is two or more atoms that are held together by chemical bonds and act as a unit. In some elements, the atoms are grouped into molecules.

9 What is a substance? (cont.) Lesson 1-4 A compound is a substance made of two or more elements that are chemically joined in a specific combination. Because each compound is made of atoms in a specific combination, a compound is a substance.

10 What is a substance? (cont.) Lesson 1-4 Many compounds exist as molecules, but some, such as table salt, do not. Sugar particles are molecules because they always travel together as a unit. Salt particles do not travel together as a unit.

11 Lesson 1-4 What is a substance? (cont.) A chemical formula includes the symbols of each element in the compound and small numbers, called subscripts, that show the ratio of the elements in the compound. Sometimes the same elements combine to form different compounds.

12 Lesson 1-4 Example of Having same Elements- organized different ways to make different substances. Does not need to go in notes.

13 What is a mixture? Lesson 1-5 A mixture is matter that can vary in composition. A mixture is made of two or more substances that are blended but are not chemically bonded.

14 Types of Mixtures Lesson 1-6 A heterogeneous mixture is a mixture in which the substances are not evenly mixed. A homogeneous mixture is a mixture in which two or more substances are evenly mixed, but not bonded together.

15 Types of Mixtures (cont.) Lesson 1-6 A solution is another name for a homogeneous mixture and is made of two parts a solvent and one or more solutes. The solvent is the substance that is present in the largest amount, and the solutes dissolve, or break apart, and mix evenly in the solvent.

16 Compounds v. Mixtures Lesson 1-6 Compounds and solutions are alike in that they both look like pure substances. The atoms that make up a given compound are bonded together, which means the composition of a given compound is always the same.

17 Compounds v. Mixtures (cont.) Lesson 1-6 The substances that make up a mixture are not bonded together. Adding more of one substance to a mixture does not change the identity of the mixture.

18 Lesson 1-6 Copy into Notebook pg 23

19 Compounds v. Mixtures (cont.) Lesson 1-6 The substances that make up a mixture are not chemically combined. The substances that make up a mixture can easily be separated by physical processes. The elements that make up a compound can be separated only by chemical processes.

20 Compounds v. Mixtures (cont.) Lesson 1-6 To separate a heterogeneous mixture, you use differences in the physical properties of the parts. The McGraw-Hill Companies, Inc./Stephen Frisch, photographer

21 Compounds v. Mixtures (cont.) Lesson 1-6 You can separate some homogeneous mixtures by boiling or evaporation. The McGraw-Hill Companies, Inc./Stephen Frisch, photographer

22 Visualizing Classification of Matter Lesson 1-6 Matter can be classified as either a substance or a mixture. Matter is classified according to the types of atoms and the arrangement of atoms in matter.

23 Lesson 1-6 Copy into notebook pg 25- important to know and study!