Chemistry Vocabulary

1. Acid a substance that produces hydrogen ions in aqueous solution; a proton donor.
2. Alkali metal a Group 1 metal.
3. Alkaline earth metal a Group 2 metal.
4. Alkane a saturated hydrocarbon with the general formula C_nH_2n12.
5. Avogadro's number the number of atoms in exactly 12 grams of pure 12C, equal to 6.02 x 10²³.
6. Base a substance that produces hydroxide ions in aqueous solution; a proton acceptor.
7. Bond (chemical bond) the force that holds two atoms together in a compound.
8. Bond energy the energy required to break a given chemical bond.
9. Bond length the distance between the nuclei of the two atoms that are connected by a bond.
10. Bonding pair an electron pair found in the space between two atoms.
11. Calorie a unit of measurement for energy; one calorie is the quantity of energy required to heat one gram of water by one Celsius degree.
12. Calorimetry the science of measuring heat flow.
13. Density a property of matter representing the mass per unit volume.
14. Electron a negatively charged particle that occupies the space around the nucleus of an atom.
15. Electronegativity the tendency of an atom in a molecule to attract shared electrons to itself. 
16. Energy the capacity to do work or to cause the flow of heat. 
17. Gas one of the three states of matter; has neither fixed shape nor fixed volume.  
18. Halogen a Group 7 element.  
19. Hydrocarbon a compound of carbon and hydrogen. 
20. Ideal gas a hypothetical gas that exactly obeys the ideal gas law.
    A real gas approaches ideal behavior at high temperature and/or low pressure. 
21. Ion an atom or a group of atoms that has a net positive or negative charge. 
22. Ionic bonding the attraction between oppositely charged ions. 
23. Joule a unit of measurement for energy; 1 calorie 5 4.184 joules. 
24. Ketone an organic compound containing the carbonyl group bonded to two carbon atoms. 
25. Lipids water-insoluble substances that can be extracted from cells by nonpolar organic solvents. 
26. Liquid one of the three states of matter; has a fixed volume but takes the shape of its container. 
27. Mass the quantity of matter in an object. 
28. Matter the material of the universe. 
29. Metal an element that gives up electrons relatively easily and is typically lustrous, malleable, and a good conductor of heat and electricity 
30. Noble gas a Group 8 element 
31. Orbital a representation of the space occupied by an eletron in an atom; the probability distribution for the electron. 
32. Organic acid an acid with a carbon-atom backbone and a carboxyl group. 
33. Organic chemistry the study of carbon-containing compounds (typically containing chains of carbon atoms) and their properties. 
34. Oxidation an increase in oxidation state (a loss of electrons). 
35. Oxidation - reduction (redox) reaction a reaction in which one or more electrons are transferred. 
36. Proton a positively charged particle in an atomic nucleus. 
37. Pure substance a substance with constant composition 
38. Salt an ionic compound. 
39. Salt bridge a U-tube containing an electrolyte that connects the two compartments of a galvanic cell, allow- ing ion flow without extensive mixing of the different solutions. 
40. Saturated solution a solution that contains as much solute as can be dissolved in that solution.