Atoms, Matter & Molecules

1. Atoms, Matter & Molecules Chapter 4

2. Observations Direct evidence obtained through use of the senses.

3. Inference A hypothesis, drawn from observations, that attempts to explain or to make sense of the observations

4. ATOM The smallest particle into which an element may be divided and still be the same substance.

5. ATOM The smallest part you can break Hydrogen (an element) into and still have Hydrogen.

6. Matter Anything that has mass and takes up space. Energy is NOT matter

7. Matter is divided into 4 components: • Elements • Compounds • Mixtures • Solutions

8. ELEMENT All elements are on the Periodic Table All matter is made of an element or a combination of elements Hydrogen, Oxygen, Gold A substance that consists of only one kind of atom and that cannot be chemically separated into other substances.

9. Elements: • E l e m e n t s c a n n o t b e c h a n g e d i n t o s i m p l e r s u b s t a n c e s b y a n y c h e m i c a l p r o c e s s . • E l e m e n t s a r e m a d e u p o f a t o m s .

10. simplest kind of matter Cannot be broken down into simpler All one kind of atom. There are 109 of these known to man Elements:

11. T y p e s o f m a t t e r • C o m p o u n d s - P u r e s u b s t a n c e s m a d e u p o f m o r e t h a n o n e e l e m e n t .

12. Compounds: • substances that can be broken down by chemical methods • When they are broken down, the pieces have completely different properties than the compound. • Made of molecules- two or more atoms

13. They are pure substances put together by chemically combining elements Not all combinations of elements are compounds though– some can be mixtures! Compounds:

14. So remember… • ELEMENTS contain only one kind of atom • There are 109 different kinds of elements • 1-109 = atomic # of the elements.

15. Solutions: • S o l u t i o n s - A s p e c i a l m i x t u r e f o r m e d w h e n o n e s u b s t a n c e d i s s o l v e s i n a n o t h e r .

16. Solutions: • S o l v e n t - t h e m o s t a b u n d a n t s u b s t a n c e i n t h e s o l u t i o n . • S o l u t e - t h e l e a s t a b u n d a n t s u b s t a n c e i n t h e s o l u t i o n .

17. A l l s o l u t i o n s a r e n o t l i q u i d s : • A i r i s a s o l u t i o n o f g a s e s . • S t e e l i s a s o l u t i o n o f m e t a l s .

18. Solutions • Homogeneous mixture • Mixed molecule by molecule • Can occur between any state of matter. • Solid in liquid- Kool-aid • Liquid in liquid- antifreeze • Gas in gas- air • Solid in solid - brass • Liquid in gas- water vapor

19. Solutions • Like all mixtures, they keep the properties of the components. • Can be separated by physical means • Do not scatter light! • Not easily separated- • but can be separated.

20. Two techniques for separating solutions: #1. Evaporation: changing from a liquid to vapor state– leaves behind the other component.

21. #2. Distillation: • Process used to drive vapor from liquid by heating • Great for separating two or more liquids which have different boiling points.

22. MIXTURE • Matter that can be physically separated into component parts • It is two or more kinds of matter that have separate identities because of their different properties.

23. When different parts of a mixture can no longer be separated into simpler substances, we call each component a PURE SUBSTANCE

24. There are two types of mixtures: • Heterogeneous- mixture is not the same from place to place. • Chocolate chip cookie, gravel, soil. • Homogeneous- same composition throughout. • Kool-aid, air. • Every part keeps its properties.

25. Mixtures: • Matter that consists of two or more substances mixed together: but not chemically combined or bonded. • Examples: concrete, Sea Water, a bag full ofdifferentcolored marbles..

26. Heterogeneous Mixture: a mixture that does not appear the same throughout. (the individual substances are visible). Ex. Soil, Raisin Brand, Chicken Noodle Soup. Heterogeneous Mixture: a mixture that appears uniform throughout. (well mixed). Ex. Stainless Steel (Cr, Fe), There are 2 types of Mixtures

27. T y p e s o f m a t t e r • P r o p e r t i e s o f M i x t u r e s : • E a c h s u b s t a n c e r e t a i n s i t s o w n p r o p e r t i e s . • S u b s t a n c e s c a n b e p r e s e n t i n a n y a m o u n t . • S u b s t a n c e s c a n b e s e p a r a t e d b y s i m p l e p h y s i c a l m e a n s.

28. Which is it? Element

29. Which is it? COMPOUND • Water is a compound formed from two hydrogen atoms and one oxygen atom chemically combined. H20

30. Which is it? MIXTURE

31. Decide if the substance is an E l e m e n t , c o mp o u n d , m i x t u r e , o r s o l u t i o n? 1. Water 1. Compound 2. Compound 2. Salt 3. Element 3. Oxygen 4. Mixture 4. Dirt 5. Solution 5. Air Click Mouse button to see answers!

32. Decide if the substance is an E l e m e n t , c o mp o u n d , m i x t u r e , o r s o l u t i o n? 6. Copper 6. Element 7. Solution 7. Coke 8. Solution 8. Steel 9. Mixture 9. Sleet 10. Mixture 10. Ice-cream Click Mouse button to see answers!

33. What about MOLECULES? These are MULTI-ATOM particles They are the smallest particle of a substance that still retains the properties of that substance and is composed of 2 or more atoms.

34. MOLECULE Particle of matter that is made up of two or more atoms.

35. MOLECULE The smallest part you can break water (a compound) into and still have water.

36. Particle Charge Location Mass Proton+ nucleus heavy Neutron 0 nucleus heavy Electron - energy levels very light

37. 17 Cl Chlorine 35.453 Atomic Number The number of protons in the nucleus

38. 17 Cl Chlorine 35.453 Atomic Mass The number of protons PLUS the number of neutrons

39. 17 Cl Chlorine 35.453 Atomic Number: 17 Number of Protons: 17 Number of Electrons: 17 Atomic Mass: 35 Number of Neutrons: 18

40. 17 p+ 18 n0