Across
- 2. this property of metal is due to the shininess of it
- 4. the electrons with the most energy that are involved in making bonds are called ____ electrons
- 5. the energy needed to remove the outermost electron of an atom
- 7. ions that have bonded to form ionic compounds are electrically _____
- 8. this type of bond forms between positive and negative ions
- 10. Mendeleev created the first PT by arranging elements in order of increasing ___ ____
- 12. hydrogen is usually shown in Group one, on the side with metals, but it is actually a ____
- 14. in a triple bond, this many electrons are shared between atoms
- 18. this is the small center of an atom
- 20. elements in the same group have ____ properties
- 23. we use this model to show how all the electrons in an atom are arranged in energy levels, he said like the orbits of planets around the sun
- 25. each element on the PT is given a unique ___ to represent that element
- 27. matter that is composed of ONE type of atom
- 28. this method is writing the element’s symbol then showing dots to represent the number of valence electrons
- 29. ions that are made of more than one atom are called this, like CO3-2
- 31. the mass of an electron is so ___ that it is not even considered in determining the weight of an atom
- 32. this is group 18, the most unreactive elements
- 34. when naming compounds and molecules of atoms that have bonded together, you change the ending of the last element with these 3 letters
- 37. a stable atom is one that has ___ valence electrons in its outer energy level (H, He, Li, and Be are exceptions)
- 40. came up with the Atomic theory and 4 statements about atoms
- 41. these metals are found in group 2
- 42. when naming covalently bonded atoms, you name the molecule using a ____ to show how many atoms of that element there are , like P4O would be Tetraphosphorus, monoxide
- 43. horizontal rows on the PT are called this
- 44. in a single covalent bond, ___ electrons are shared between atoms
- 46. Atoms of the same element that have different number of neutrons
- 50. in a neutral atom, the number of protons equals the number of ____
- 53. the ___ metals are groups 3-12 on the PT
- 56. telling me that Sodium’s electrons are arranged as 2,8,1 is telling me Sodium’s electron _____
- 59. if an element has 8 valence electrons naturally, or if it bonds with another atom to acquire 8, then it is called ___
- 60. a number assigned to an element that represents the number of electrons lost (or gained, if the number is negative) by an atom of that element in the compound for it to become stable
- 61. these elements on the PT are malleable, ductile, and can carry an electric current
- 62. an atoms ability to attract electrons to itself when bonding to another atom
- 63. in a double covalent bond, this many electrons are shared between atoms
- 64. his uncertainly principal stated that you cannot be certain where an electron is at any one point
Down
- 1. F, Cl, and Br belong to Group 17, also called the ____ group
- 3. these metals are found in group 1
- 4. molecules can attract to each other through the slightly positive and negative ends of polar covalent molecules, these are called __ __ ___ forces
- 6. columns on the PT are called this
- 9. a covalent bond where atoms are sharing electrons equally
- 11. what information on a block on the PT tells you how many protons that element has in its atoms
- 13. the mass of an atom is the sum of all it’s isotopes on earth and the units used to express it are ___ ___ ___
- 15. discovered the neutron
- 16. came up with the electron cloud model of the atom
- 17. discovered the nucleus and proton and named them both, said the atom is a lot of empty space, had the gold-foil experiment
- 19. this, in a chemical formula tells you how many atoms of an element are present
- 21. this means that a metal can be hammered into very thin sheets
- 22. protons carry this charge
- 24. used the word “atomos” and said there are particles so small they cannot be cut into anything smaller
- 26. this bond happens when electrons are shared between atoms
- 30. he was the first to arrange elements into a periodic table
- 33. electrons carry this charge
- 35. a charged atom is called this
- 36. came up with the “plum-pudding” model of the atom
- 38. these metals are found in groups 3-12
- 39. elements known as ___ are shown to the right of the metalloids on the PT
- 45. a covalent bond where one atom is pulling the electrons more towards it, so the sharing is unequal, it makes the molecule slightly charged
- 47. when an atom loses an electron it becomes a ___ ion
- 48. a metal is called this because it can be drawn out into thin wire
- 49. the atomic mass is the average mass of an atom of that elements protons and ____
- 51. the atomic number of an element is based on the number of __ in one atom of that element
- 52. at room temperature, most metals are in this state of matter
- 54. metals are good ____ of heat and electricity
- 55. elements that have some properties of metals and some of nonmetals
- 57. elements in the same period have the same ____ of electron energy levels (orbitals)
- 58. he arranged the modern day PT