Chemistry Vocabulary Cards

1. Chemistry Vocabulary Cards

2. Physical property • Definition: A quality or characteristic of a substance that can be observed or measured WITHOUT changing the substance’s composition. • Example: Physical properties include: color, solubility, odor, hardness, density, melting and boiling point

3. Chemical property • Definition: The ability of a substance to undergo a chemical reaction and to form new substances • Example: Rusting is a chemical property of iron

4. Density • Definition: The amount of mass that is contained in a given volume of a substance. • Example: A rock is more dense than water, because a given volume of rock has more mass than the same given volume of water

5. Malleability • Definition: how easily something can be hammered into thin sheets • Example: Aluminum is more malleable than iron

6. Ductility • Definition: How easily something can be pulled into thin wires • Example: Copper wire is used in many electronic devices because it is very ductile compared to other metals

7. Flammability • Definition: Easily set on fire, combustible • Example: Gasoline is highly flammable

8. Rusting • Definition: Any film or coating on metal caused by oxidation • Example: the red or orange coating that forms on the surface of iron when exposed to air and moisture is rust

9. Solubility • Definition: The maximum amount of a substance that will dissolve in a given amount of solvent at a given temperature. • Example: Sugar is soluble in a glass of water or tea

10. Element • Definition: A basic building block of matter that cannot be broken down into simpler substance • Example: Gold is an element. Gold atoms are the simplest form of gold.

11. Compound • Definition: A substance that can be separated into simpler substances (elements and other compounds) • Example: A water molecule is a compound consisting of 2 hydrogen atoms and 1 oxygen atom

12. Mixture • Definition: A grouping together of two or more substances in which each retains its original properties • Example: A salad, a bowl of chicken noodle soup or blood are examples of mixtures

13. Specific Heat • Definition: The quantity of heat, in joules or calories, required to raise the temputure of 1g of a substance by 1 degree • Example: 1 calorie of heat is needed to raise 1 gram of water by 1 degree Celcius, so the specific heat capacity of water is 1 calorie.

14. Conductor • Definition: a substance, body, or device that readily conducts heat, electricity, sound, etc. • Example: Copper is a good conductor of heat

15. Insulator • Definition: a material that is a poor conductor of electricity or heat. • Example: A Styrofoam cup is an used as insulator to either keep a hot drink warm or a cold drink cool.

16. Chemical change • Definition: any change from one state (gas, liquid, solid) which is accompanied by alteration of the chemical composition; any process in which one or more substances are changed into one or more different substances • Example: A chemical change is when you burn wood and the wood becomes ash

17. Physical change • Definition: Physical changes are changes that do not change the chemical composition of a substance. No new products are formed. • Example: Cutting, grinding and bending are all physical changes.

18. Precipitate • Definition: to separate from solution or suspension • Example: 2 liquid compounds were mixed and a precipitate was formed

19. Metals • Definition: A class of elements that tends to lose electrons, forming positive ions, and is a good electrical and/or heat conductor. • Example: Magnesium, lithium and potassium are all metals

20. Nonmetals • Definition: A class of elements that aren’t lustrous, usually poor conductors of heat and electricity • Example: Carbon, nitrogen and oxygen are all nonmetals

21. Metalloids • Definition: An element with properties intermediate between metals and non-metals • Example: Silicon and germanium are metalloids

22. Periods • Definition: The horizontal rows of the periodic table, there are 7 periods • Example: Elements lithium through neon compose of period two of the periodic table

23. Groups • Definition: The vertical columns of the periodic table, there are 7 groups • Example: Elements hydrogen through francium compose of group one of the periodic table

24. Atom • Definition: The smallest unit of an element which has all the properties of the element. It is composed of protons, neutrons and electrons • Example: If you took a copper penny and ground it into copper dust, then you continued to divide the copper dust particles, you would eventually come upon a particle of copper that could no longer be divided and yet still retain the properties of copper, this final particle would be an atom of copper

25. Proton • Definition: A positively charged subatomic particle found in the nucleus neutron

26. Neutron • Definition: A subatomic particle found in the nucleus that has no charge

27. Electron • A negatively charged subatomic particle, of extremely low mass found in the space outside the nucleus of an atom.

28. Valence electrons • An electron in the highest occupied energy level (orbital) of an atom • Example: hydrogen has 1 valence electron in its highest occupied energy level (orbital)

29. Ion • Definition: An electrically charged particle formed by the gain or loss of electrons • Example: Sodium tends to lose one of its electrons during a compound formation, causing the number of electrons to no longer be equal to the number protons, it is now a positively charged sodium ion because there are more protons than electrons

30. Ions

31. Isotope • Definition: Compounds with the same molecular formulas but the atoms are arranged differently from one another • Example: H2 and H3 are isotopes of the element hydrogen

32. Atomic Number • Tells you the number of protons in the nucleus in the atom. Atomic Number

33. Atomic Mass • Tells you the total number of protons and neutrons in an atom Atomic Mass

34. Symbol • 1 to 2 letter abbreviations for the elements on the periodic table • Al is the symbol for the element aluminum Symbol

35. Chemical Formula • Definition: The chemical formula identifies each element by its chemical symbol and indicates the number of atoms of each element found in each molecule of that compound • Example: Chemical formula for water is H20, composing of 2 atoms of hydrogen and 1 atom of oxygen

36. Reactants • A starting substance(s) in a chemical reaction

37. Products • Definition: the substance(s) formed in a chemical reaction

38. Coefficients • Definition: Large number that appears in front of a chemical formula in a balanced chemical equation, tells you how many molecules of a particular substance is present • Example: chemical formula 2H20 tells you there are 2 molecules of water present (underlined number is coefficient)

39. Subscripts • Definition: Small number that appears behind a particular symbol of a chemical formula in a balanced chemical equation, tells you how many atom of that particular atom that are present • Chemical formula H20 tells you there are 2 atoms of hydrogen present (underlined number is subscript)

40. Chemical Equation • An expression representing a chemical reaction, the formulas of the reactants on the left of the arrow and the formulas of the of the products on the right of the arrow

41. Law of Conservation of Mass • Definition: Mass can be neither created nor destroyed in an ordinary chemical or physical process • The number of atoms of an element or compound in the reactants will equal the number of atoms of an element or compound in the products. No matter how the substances are redistributed

42. Octet Rule • States that all atoms want to either have 8 or no valence electrons in their outer shell to become stable. Neon (8 valence e-)