Across
- 4. a change of one or more substances into new substances
- 5. a reaction in which a compound breaks down into two or more simpler substances
- 7. a strong base
- 9. an electron in the outermost energy level of an atom; electrons that are gained or lost to form ions
- 13. in a covalent compound, electrons are ____ between two atoms
- 15. group 17 nonmetal
- 17. an indicator solution that is clear in acids and neutral solutions, but turns pink in basic solutions
- 18. a substance that changes color in the presence of acids or bases
- 20. indicator paper that turns red in the presence of acids or blue in the presence of bases
- 21. a reaction in which two or more reactants combine to form a single product
- 22. chemical reaction that absorbs energy
- 23. any compound that conducts electricity when melted or dissolved in water
- 24. in an ionic compound, electrons are ____ from the metal to the nonmetal
- 28. a number placed in front of the substances of a chemical equation to indicate how many are involved
- 34. ____ acids and bases are found at the far ends of the pH scale
- 35. ____ acids and bases are found towards the middle of the pH scale
- 36. a type of compound that contains nonmetals only
- 39. a substance that undergoes a chemical change
- 40. a reaction in which a hydrocarbon reacts with oxygen to produce carbon dioxide and water
- 42. a strong acid
- 43. a type of element that loses electrons to form an ion
Down
- 1. a substance that produces hydroxide ions when dissolved in water
- 2. Group 1 metal
- 3. an organic compound that consists of hydrogen and carbon
- 6. atoms gain or lose electrons to become ___
- 8. a displacement reaction in which the positive and negative portions of two ionic compounds are interchanged
- 10. a number used to indicate how many atoms of a given element are in a compound
- 11. a scale from 0 to 14 that measures the strength of acids and bases
- 12. an ion that consists of two or more different elements
- 14. Group 2 metal
- 16. the smallest particle of an element
- 19. a type of element that gains electrons to form an ion
- 25. Group 18 element with a full valence shell
- 26. a substance that produces hydrogen ions when dissolved in water
- 27. a displacement reaction in which one element takes the place of another in a compound
- 28. a positive ion
- 29. a type of compound formed between a metal and a nonmetal
- 30. chemical reaction that releases energy
- 31. a combination of chemical symbols that show what elements make up a compound and the number of atoms of each element
- 32. a chemical combination of two or more different elements
- 33. rule that states that atoms become stable by having eight electrons in their outer energy level
- 37. a new substance formed when substances undergo a chemical change
- 38. a negative ion
- 41. an atom or group of atoms that has a charge because of the loss or gain of electrons