Chem test Flashcards
groups
vertical columns labelled 1-18
periods
horizantal columns labelled 1-7
physical change
same substance with altered attributes
chemical change
change in which 1 or more new substamces are created
alkali earth metals
never found uncombined in nature, has two valance electrons
alkali metals
first column, shiny, 1 valence electron
transition metals
good conductors, popular metals
halogens
17th column, 7 valence electrons, most active non-metals
noble gasses
extremely unreastive, full outer orbit, dont combine so called inert
rare earth metals
bottom of the periodic table
cation
ions with a postive charge
anion
ions with a negative charge
valence electrons
electrons found in the outermost orbit, electrons involved in sharing or combining
ionic bonds
the complete tranfer of electrons from one atom to another
covalent bonds
the sharing of one or more pairs of electrons
diatomic elements/molecules
2 atoms of the same type form a stable covalent molecule. (HOFBrINCl)
reactant
what you start with in a chemical equation
product
what you end up with
law of conservation of mass
the mass of the reactants needs to be equal to the mass of the products
5 types of chemical reactions
synthesis, decompostion, double and single displacemtent and combustion
combustion
reaction wher hydrocarbon burns in oxygen to produce water and carbon dioxide
incomplete combustion
hydrocarbon burns in water to prodice a misture of products (not enough oxygen)
acid
ph of less than 7, releases hydrogen in water
base
ph of more than 7, releases hydroxide in water
properties of an acid
reactive, explosive,sour tasting
properties of a base
reactive, corrosive, bitter tasting
pH
a measure of how acidic or basic a substance is
neutralization reaction
when an acid reacts with a base to make it neutrual
acid rain
when nitrogen and sulfur is released which combines with oxygen to form nitrogen oxides and sulfur dioxide
non metallic elemants form…
anion
metallic elements form…
cations
