chapter 7 test Flashcards
valence electrons
electrons in the outmost energy level
octet rule
atoms when forming compounds, through chemical bonds, tend to achieve the electron configuration of a novel gas and a “stable octet” by having 8e- in the outermost energy level
atoms of metals tend to ____ electrons and form _____
lose; cations
atoms of nonmetals tend to ____ and form _____
gain; anions
ionic bond
attraction between positive and negative ions through transfer of electrons
ionic compounds are between:
a nonmetal and metal
covalent bons form between:
two nonmetals
formula unit
lowest whole number ratio of ions in an ionic compound
ionic compounds form ____
crystals
3 properties of ionic compounds:
- crystalline solid at room temp
- high melting point
- can conduct an electric current when melted or dissolved in water
coordination number
number of oppositely charged ions that surround an ion in the crystal; specific to compound
ionic compounds when melted/dissolved ____ conduct electricity
CAN
why can ionic compounds when melted/dissolved conduct electricity?
because the ions move freely
ionic compounds when solid ______ conduct electricity
CAN NOT
why can’t ionic compounds when solid conduct electricity?
because the ions can’t move and are fixed in place
electrolytes
ionic compounds dissolved in water
when metals react together what do they form?
homogenous mixtures called alloys
ionic compound
compound composed of cations and anions
alloy
a mixture of two or more elements at least one of which is a metal
metallic bond
the attraction of the free floating valance electrons for the positively charged metal ions (sea of e-)
chemical formula
shows the kinds and numbers of atoms in the smallest representative unit of a substance
in general, metals react by:
losing valence electrons
