1				2																			3
4				5				6							7						8
																	9
											10
				11
											12
													13
	14
										15										16	17								18
19
								20
													21
				22		23
24								25															26
		27
																						28
				29																30
																				31
										32
33																						34							35
								36
			37														38
													39
																			40

Across 4. A measure of how difficult it is to stretch or break the surface of a liquid. (2 Words) 8. A substance containing two or more elements in a fixed ratio. Ex: table salt (NaCl) consists of one atom of the element sodium (Na) for every atom of chlorine (Cl) 10. A measure of the intensity of heat in degrees, reflecting the average kinetic energy or speed of molecules. 11. One of several atomic forms of an element, each with the same number of protons but a different number of neutrons. 12. A covalent bond between atoms that differ in electronegativity. (3 Words) 13. A chemical bond resulting from the attraction between oppositely charged ions. (2 Words) 16. The sum of the number of protons and neutrons in an atom's nucleus (2 Words) 19. The dissolving agent of a solution. 20. The making and breaking of chemical bonds, leading to changes in the composition of matter. (2 Words) 21. A solution in which water is the solvent. (2 Words) 25. A covalent bond in which electrons are shared equally between two atoms of similar electronegativity. (3 Words) 28. Anything that occupies space and has mass 29. An attraction between two atoms resulting from a sharing of outer-shell electrons or the presence of opposite charges on the atoms. The bonded atoms gain complete outer electron shells. (2 Words) 31. The attraction between different kinds of molecules 32. An atom or a group of atoms that has gained or lost one or more electrons, thus acquiring a charge. 33. A substance that cannot be broken down to other substances by chemical means. 34. A subatomic particle with a single negative electrical charge. One or more ___ move around the nucleus of an atom. 37. A strong chemical bond in which two atoms share one or more pairs of outer-shell electrons. (2 Words) 38. The total mass of an atom. Given as a whole number, the atomic mass approximately equals the mass number. (2 Words) 39. A type of weak chemical bond formed when the partially positive hydrogen atom participating in a polar covalent bond in one molecule is attracted to the partially negative atom participating in a polar covalent bond in another molecule. (2 Words) 40. The sticking together of molecules of the same kind, often by hydrogen bonds.

Down 1. An ending material in a chemical reaction. 2. A subatomic particle having no electrical charge, found in the nucleus of an atom 3. A molecule containing polar covalent bonds and having unequal distribution of charges. (2 Words) 4. A liquid that is a uniform mixture of two or more substances. 5. The number of protons in each atom of a particular element (2 Words) 6. The process in which the surface of an object becomes cooler during evaporation. (2 Words) 7. An energy level representing the distance of an electron from the nucleus of an atom. (2 Words) 9. An isotope whose nucleus decays spontaneously, giving off particles and energy. (2 Words) 14. A subatomic particle with a single positive electrical charge, found in the nucleus of an atom. 15. The attraction of a given atom for the electrons of a covalent bond. 17. A substance that increases the hydrogen ion (H+) concentration in a solution 18. A starting material in a chemical reaction. 22. Two or more atoms held together by covalent bonds. 23. A chemical substance that resists changes in pH by accepting hydrogen ions from or donating hydrogen ions to solutions. 24. A measure of the relative acidity of a solution, ranging in value from 0 (most acidic) to 14 (most basic). (2 Words) 26. An element that is essential for life but required in extremely minute amounts. (2 Words) 27. A substance that is dissolved in a solution. 30. A substance that decreases the hydrogen ion (H+) concentration in a solution. 35. An atom's central core, containing protons and neutrons. 36. Thermal energy; the amount of energy associated with the movement of the atoms and molecules in a body of matter. ___ is energy in its most random form. 38. The smallest unit of matter that retains the properties of an element.