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1. After the Big Bang occurred, the first element formed was: 2. They then gravitated together into stars and fused together forming larger elements. The 5 mentioned in the video were: 3. The end of a star’s life results In a huge explosion called a: 4. As a result of the explosion, were formed. 5. Krypton and Xenon are part of a larger group called: 6. When the elements are organized, they line up with i. and on the left and on the right don’t fit into either category. They are “in between.” 7. How do the elements arrange themselves: 1. Left to right? 2. Top to bottom? 8. This arrangement of atoms matches up with what well known structure? 9. Oxygen atoms are so chemically reactive that they are not found in nature as single atoms. They pair up with each other and form what type of particle? 10. What are the chemical formulas for these particles? 11. Do noble gases pair up with other elements? 12. Do metals form molecules? If not, in what forms can they take? 13. The video tries to use modeling as a way for you to understand the different changes. a. What do they say presents a physical change? b. A chemical change? 14. What is the formula of the compound when hydrogen chemically combines with carbon? a. What is the name of this molecule? 15. What is the formula of the compound when hydrogen chemically combines with nitrogen? a. What is the name of this molecule? 16. What happens when hydrogen “marries” oxygen? 17. Why is this marriage considered “forever”? 18. What happens when sodium “marries” chlorine? 19. What is an ion? 20. What is a salt? 21. Does salt form a molecule? 22. At the atomic level, what happens to the salt when it is added to water? 23. How does the water molecule arrange itself next to the chloride ion? 24. The sodium ion? 25. Is this a physical or a chemical change? Explain. 26. How can this change be reversed? 27. What happens to the sodium and chloride ions? 28. How else can the sodium and chloride ions be separated? 29. Is this a physical or a chemical change? Why? 30. How can the sodium and chloride ions be permanently separated (get “Divorced”)? 31. What makes this change “permanent”? 32. What other compound can electrolysis separate? 33. The process of separating liquid water into water vapor (gas phase) is what kind of change? Why? 34. When carbon atoms join together, this lubricant is formed 35. Is this a chemical change? 36. What is another form of carbon atoms joined together? 37. What physical property does this material have? 38. Buckyballs and buckytubes are made of what element? 39. When silicon combines with 4 oxygen, quartz if formed. This is the second most abundant mineral in the earth’s : 40. If a change occurs and there is no change in combination of the atoms (chemical composition), this change is called: 41. What happens with copper mixes with zinc? 42. What kind of change is this? Why? 43. A mixture of metals is called an: 44. Why are pots and pipes made out of copper? 45. How can we make iron stronger? 46. What is this new mixture called? 47. Is the formation of mixtures is a chemical or physical change?