Periodic Table
What are the 3 main sections of the Periodic Table?
metals, nonmetals, and metalliods
What are the electrons on the outer level of an atom called?
valence electrons
What kind of reaction has two reactants and two products?
single-replacement reaction
What does pH stand for?
potential for Hydrogen
What is the number placed in front of an element symbol or chemical formula in an equation called?
coefficient
What are the columns called on the Periodic Table?
group or family
What kind of bond is between positively and negatively charged atoms?
ionic bond
Distinguish between endothermic and exothermic reactions.
endothermic = absorbs energy/heat
exothermic = releases energy/heat
Temperature and pressure can change what component of a solute?
solubility
What is the small number placed after an element in a chemical equation called?
subscript
What are the rows called on the Periodic Table?
periods
What has a slightly positive end and a slightly negative end because of unequal sharing of electrons?
polar molecule
What kind of reaction occurs when a substance combines with oxygen and releases energy?
combustion
What kind of mixture has individual components that you can see?
heterogeneous
What does the arrow mean in a chemical equation?
a reaction has happened
What is special about electrons of atoms in the same group/family?
same number of valence electrons
What kind of bond is formed when positively charged atoms share their electrons.
metallic bond
What lowers the activation energy of a reaction or chemical formula in an equation?
catalyst
What kind of mixture has individual parts that you cannot see?
homogeneous
O2 + 4H3
How many hydrogen atoms are in the formula?
12
What information is on one tile of the Periodic Table?
element name, element symbol, atomic number, and atomic mass
covalent bond
What is the name of the starting substance and produced substance of a chemical reaction?
reactant and product
What do bases and what do acids release in a solution?
base: hydroxide ions
acid: hydrogen ions
Balance the chemical equation.
___ Li + ___ F2 --> ___ LiF
_2_ Li + ___ F2 --> _2_ LiF