click below
click below
Normal Size Small Size show me how
McC 8 Chem Ch 3
| Term | Definition |
|---|---|
| period | horizontal row of elements in the periodic table whose properties change gradually and predictably |
| group | family of elements in the periodic table that have similar physical or chemical properties |
| representative elements | elements in Groups 1 & 2, and 13 - 18 in the periodic table that include metals, metalloids and nonmetals |
| transition elements | elements in Groups 3 - 12 in the periodic table, all of which are metals |
| metal | element that has luster, is malleable and ductile, is a good conductor of heat and electricity |
| metalloid | element that shares some properties with metals and nonmetals |
| nonmetals | element that is usually a gas or brittle solid at room temperature and is a poor conductor of heat and electricity |
| How did Mendeleev arrange the periodic table? | by increasing atomic mass |
| How did Moseley arrange the periodic table? | by increasing atomic number |
| How is the modern periodic table arranged? | by increasing atomic number |
| Where are metals located on the periodic table? | to the left of the stair step line |
| Where are the nonmetals located on the periodic table? | to the right of the stair step line plus Hydrogen |
| Where are the metalloids located on the periodic table? | along the stair step line except Aluminum which is a metal |
| oxidation number | the number of electrons an atom will gain, lose or share in order to bond and complete its outer energy level. A '+' means the atom will LOSE electrons. A '-' means the atom will GAIN electrons. |
| valence electrons | electrons in the outer most energy level |
| ionic bond | bond between metals and nonmetals |
| covalent bond | bond between nonmetals or 2 atoms of the same element |
| metallic bond | bond between metals |
| What is the maximum number of valence electrons? | 8 |
| Where do you look on the periodic table to quickly tell the number of energy levels an element has? | the period number |
| Where do you look on the periodic table to quickly tell the number of valence electrons an element has? | at the one's place of the group number - Group 1 has 1 valence electron - Group 17 has 7 valence electrons |
| Octet Rule | atoms gain, lose or share electrons until they have a full outer shell (most need 8 valance electrons to be stable) Hydrogen and Helium are exceptions |
| '+' oxidation number | a '+' means an atom will lose electrons |
| '-' oxidation munber | a '-' means an atom will gain electrons |
| properties of metals | shiny, ductile, malleable,conductor of heat & electricity |
| properties of nonmetals | dull, brittle, insulator |
| properties of metalloids | properties of both metals & nonmetals |
| When you are making a compound, the oxidation numbers should add up to what number? | 0 |
| synthetic | elements made in a lab |