substances and mixtures.pptx grade 6 integrated science

substances and mixtures.pptx grade 6 integrated science

1. Chapter 11 Lesson 1

2. substances

3. A substance is matter that is always made up of the same combination of atoms. There are two types of substances — elements and compounds . The composition of elements and compounds doesn’t change. Therefore, all elements and compounds are substances. substances

4. substances https://www.youtube.com/watch?v=olNaHLbd8zg

5. Elements An element is a type of matter made of just one kind of atom. Elements are pure substances.

6. Elements All atoms of an element have the same number of protons. For example , boron is an element. Every atom of boron contains exactly five protons. No other element has atoms with exactly five protons. Examples of elements include neon, mercury, chlorine, silver, and copper. Boron Carbon

7. Copyright © Houghton Mifflin Harcourt Publishing Company Elements are arranged in the periodic table .

8. What information is contained in each square on the periodic table? Each square contains an element’s chemical name, atomic number, chemical symbol, and atomic mass. The atomic number is placed at the top of each square. Number of protons Number of protons + neutrons

9. A compound is a pure substance formed when two or more different atoms combine . The properties of a compound are often different from the properties of the atoms that form it. For example, atoms of carbon and oxygen will react, forming the compound carbon dioxide. This compound has its own properties that are different than those of carbon or oxygen .

10. Putting It All Together Which substances are elements? Which substances are compounds?

11. mixture A mixture is two or more substances that are physically blended but are not chemically bonded together .

12. Air is also a mixture. Air contains about 78 percent nitrogen, 21 percent oxygen, and 1 percent other substances. mixture AIR

13. heterogeneous / homogeneous mixtures T wo types of mixtures— heterogeneous and homogeneous .

14. heterogeneous mixtures A heterogeneous mixture is a mixture in which substances are not evenly mixed . Often, you can see the different substances and parts of a heterogeneous mixture with unaided eyes. Sometimes you can see them only with a microscope.

15. homogeneous mixtures A homogeneous mixture is a mixture in which two or more substances are evenly mixed . Air is a homogeneous mixture. Another name for a homogeneous mixture is solution .

16. homogeneous mixtures Solvent --a substance in which another substance is dissolved (Ex: water) Solute-- the substance that is dissolved in the solvent (Ex: sugar)

17. heterogeneous mixture homogeneous mixture https://www.youtube.com/watch?v=o-XSY-jUwig

18. how do compounds and mixtures differ? The substances that make up a mixture are not chemically bonded. Mixing is a physical change. The substances that exist before mixing still exist in the mixture.

19. how do compounds and mixtures differ? S U BSTANCES KEEP TH EI R PROPERTIES Substances that make up a mixture are not changed chemically. You can observe some of their properties in the mixture. Sugar water is a mixture of two compounds—sugar and water. After the sugar is mixed in, you can’t see the sugar in the water, but you can still taste its property of sweetness. You can also observe some properties of the water, such as its liquid state.

20. how do compounds and mixtures differ? COMPOUND S D O NOT K EEP T HEI R P R OPER T IES The properties of a compound can be different from the properties of the elements that make it up. Sodium and chlorine bond and form table salt. Sodium is a soft, opaque, silvery metal. Chlorine is a greenish, poisonous gas. You cannot observe any of these properties in table salt.

21. how do compounds and mixtures differ? MIXTU RES CA N BE SEPARATED The substances that make up a mixture are not chemically bonded together. As a result, you can separate them from each other using physical methods. The physical properties of one substance are different from those of another. You can use these differences to separate the substances. In contrast, you can separate compounds only by a chemical change that breaks the bonds between the elements.

22. Ways of separating mixtures: 1-A sieve, or mesh screen, has holes that matter can pass through. Smaller matter passes through the screen while larger matter stays in the sieve.

23. Ways of separating mixtures: 2-A magnet : attracts matter that contains iron , separating it from the other parts of the mixture. Ex. Separating iron filings –sand mixture.

24. 3-Evaporation: Boiling changes a liquid to a gas at the liquid’s boiling point. Evaporation changes a liquid to a gas below the liquid’s boiling point. During boiling and evaporation, liquid particles leave the solution while dissolved particles stay behind.

25. 4-Filteration: Filters have tiny openings, or pores, where only the smallest bits of matter, like water particles, can pass through.

26. mixtures