How do distinguish one element from another?
Number of atoms
Number of electrons
Number of portons
All of the above
Which of these is NOT a homogeneous mixture?
Solution
Suspension
Colloid
A mixture ___ a chemical combining of substances.
is
is not
In a compound, the ____ are ____ combined.
atoms, chemically
atoms, physically
molecules, physically
molecules, chemically
Elements that make up the compound ____ their identities and ____ take on a new set of properties.
retain, do
retain, don't
lose, don't
lose, do
The smallest identifiable unit of an element is a(n) ____.
proton
atom
molecule
None of these
In a mixture, the substances involved _____ be separated by a simple physical process because the elements are ________.
can, physically combined
can, chemically combined
can not, chemically combined
can not, physically combined
In a mixture substances _____ their identities.
retain
lose
Which of these is not a heterogeneous mixture? (more than one)
raisin bread
dissolved sugar water
humans
tossed salad
Which of these is a mixture (others are pure substances)?
Hydrogen
Potassium
Neon
Sugar
An apple
Milk
What is absolute zero?
coldest possible temerature
highest possible temperature
The measurement with absolute zero is ____.
Kelvin
Fahrenheit
Celcius
The first element was _____ because it has the least amount of protons.
Helium
Oxygen
Nitrogen
The two pure substances: _____ & ____.
Nuclear Fusion, Nuclear Fission
Compound, Element
Homogeneous, Heterogeneous
Solids, Liquids
Kool-Aid mix is mixed with water until it dissolves. Which of these is correct?
Solute = Water Solvent = Kool-Aid
Solute = Kool-Aid Solvent = Water
Stars burn out when they __________.
run out of oxygen
gain to much oxygen
run out of hydrogen
gain to much hydrogen
What is the "Universal Solvent"?
Salt
Water
What are two chemical properties?
Elements, Compounds
Color change, Production of gas
Malleability, Hardness
What is the difference between endothermic and exothermic?
exothermic = heat taken in endothermic = heat released
exothermic = heat released endothermic = heat taken in
No difference
Three exothermic phase changes are?
Melting
Condensation
Deposition
Evaporating
Sublimation
Freezing
Three endothermic phase changes?
