This document provides an overview of chemistry concepts including: - Atoms are made of protons, neutrons, and electrons. Protons and neutrons are in the nucleus while electrons orbit around it. - Elements are substances made of only one type of atom. Compounds are formed when elements combine via ionic or covalent bonds. - Dmitri Mendeleev is credited with creating the first recognizable periodic table in 1869, which organized elements by atomic mass and predicted new elements. - Chemical reactions involve changes in atoms or molecules and can be identified by physical changes like temperature, color, or bubbling. Reaction rates depend on factors like temperature, particle size, and stirring.

1. Chemistry

2. Contents!Elements and Atoms

3. What makes up an Atom

4. Atomic Numbers

5. Compounds (Ionic and Covalent)

6. Metals and Non Metals

7. The Periodic Table; What it is and who discovered it?

8. Chemical Reactions

9. Identifying Chemical Reactions

10. Chemical and Physical changes

11. Reaction rate and factors affecting it

12. Bibliography By Catherine

13. Elements and Atoms

14. Atoms

15. What Are AtomsAn atom is something that makes up something else.

16. Each object living or non living is somehow made up of atoms

17. An atom cannot be seen by the human eye unless with help of a very powerful microscope.

18. Atoms make up elements which then make up matter. The Structure Of An AtomAtoms are made up from Electrons, Protons and NeutronsThe centre of an atom is called the nucleus, the nucleus is basically a collection of protons and neutrons. Protons are positively charged particles and neutrons are evenly charged particles. Around the nucleus are the particles called electrons. These electrons are negatively charged and spin around the nucleus at amazingly fast speeds. Neutrons have no charge and Are stationary in the nucleus The protons and neutronsElectrons

19. What makes up an atom?ProtonsNeutronsElectrons

20. ProtonsProtons are an element of an atom and can be particles of importance and used by themselves.

21. Protons have actually been known to become neutrons from certain experiments and studies.

22. Protons are a similar size to neutrons but are much bigger then electrons. NeutronsNeutrons are found in almost every atom and have no electric charge.

23. The hydrogen atom’s nucleus is the only one without neutrons.

24. There is a minimum of one neutron in every other atom’s nucleus.

25. The existence of neutrons were first discovered by physicist James Chadwick. Electrons Electrons are the negatively charged particles which make up an atom.

26. Electrons are so fast that it is impossible, even with today’s modern technology to tell where they are at any specific time.

27. Electrons are very important in the world of electricity. ElementsElements are things made up by atoms .Hydrogen is an element, oxygen is an element. Nearly all of the elements have a place on the periodic table. Elements cannot be made any smaller by any ordinary chemical method.Elements are the building blocks of life, from elements come compounds.

28. Atomic NumbersEvery element has an atomic number. This atomic number represents the number of protons in the substance. Any element with an atomic number of 83 – 94 are thought to be unstable since they have no stable nuclei but still exist on earth. ** Nuclear substances are made up from these unstable elements.

29. CompoundsCompounds are two or more elements bounded together to make a new substance. There are 2 main types of bonds/comounds that can occur. One is the Covalent Compound the other the Ionic Compound.

30. Covalent CompoundsCovalent Compounds are compounds which when bonded together share electrons. Covalent Compounds usually occur when two non metals are joined together. There area few main factors which can usually be used to distinguish Covalent Compounds from Ionic Compounds:Covalent compounds usually have a lower boiling point to Ionic compoundsCovalent compounds are usually much more flammable then Ionic compoundsCovalent compounds don’t conduct electricity in water

31. Ionic CompoundsIonic Compounds are usually made when a non metal and a metal are bonded together. Ionic compounds are where two or more ions are joined together by a strong electrical attraction. One of the ions has a positive charge the other a negative charge. The positive charge and the negative charged are attracted to each other by the same thing that makes the north and south poles of a magnet join together. Some main characteristics of Ionic compounds are: Ionic compounds have high melting and boiling points

32. Ionic compounds are very brittle and hard

33. Ionic compounds conduct electricity when they dissolve in waterMetals and Non MetalsNon Metals: An element not having the character of a metal, as carbon or nitrogenMetals: Any of a class of elementary substances, as gold, silver, or copper, all of which are crystalline when solid and many of which are characterized by opacity, ductility, conductivity, and a unique luster when freshly fractured.

34. Chemical Properties*Generalization

35. Physical Properties*Generalization

36. The Periodic TableThe Periodic Table has developed over many years to become the comprehensive table of elements it is today. It is used to name elements and the atomic value of each of them. So let’s investigate further…..

37. Periodic Table KeyThe Periodic Table

38. The Discoverers of the Periodic Table Arsitotle- 330BCAntoine Lavoisier- 1770 to 1789Jons Jakob Berzelius- 1828Johann Dobereiner-1829John Newlands-1864Lothar Meyer-1869Dmitiri Mendeleev-1869William Ramsay-1894Henry Moseley-1914Glen Seaborg-1940

39. AristotleA lot of historical events have occurred over time to make the periodic table the extensive table it is today. The first discoverer to have come up with theory of elements is believed to be Aristotle in the BC time period. He came up with the theory of 4 elements, earth, wind, fire and water.

40. Antoine LavoisierAntoine wrote the first extensive list of elements which contained 33 elements, he also distinguished metals from non metals. Later though, some of his ‘elements’ were later described as compounds and mixtures.

41. Jons Jakob BerzeliusJons Jakob Berzelius was a Swedish chemist who is credited with the discovery of the elements, silicon, selenium, thorium and cerium.