chem Flashcards
(19 cards)
element
a type of pure substance that cannot be broken down.
compound
a type of pure substance made from two or more elements in a fixed proportion.
subatomic molecule
neutron, electron and proton
diatomic molecule
two of the same element linked together.
chemical family
related chemicals found on the same vertical column on the periodic table.
stable octet
a stable arrangement of eight electrons on the valance shell of an atom
ionic compound
a compound that is made up of positive and negative ions.
formed when electrons are transferred from a metal and a non-metal
molecular compound
a compound formed when two non-metals combine
law conservation of mass
a law that states that the mass in a chemical reaction stays the same as the product
exothermic reaction
a reaction that releases heat
ex. combustion reactions dissolving acid in water
endothermic reaction
a reaction that absorbs heat
ex. melting ice
acids
sour tasting, soluble (red)
bases
bitter tasting, soluble (blue)
indicators
substances that turn different colors in acids and bases
ex. litmus paper
pH scale
a scale numerical scale (0-14) that measures the acid or base levels of a solution
ex. acids have low pH, bases have high pH, neutral solutions have a level of 7 pH
neutralization Reaction
a double displacement reaction between an acid and a base that produces salt and water
combustion
a substance reacts with oxygen to form carbon dioxide and water (CO2 + 2 H2O)
universal indicator
changes colors as the pH of a solution changes
ex.
acid = red
base = blue
neutral = green
ous-ick
cuprous charge 1
cupric charge 2
