Grade 9 Science
Name: ____________________________
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Quiz: Density, Particle Theory and Classifying Matter
1) Explain why pure water floats on salt water.
(2)
2) Explain, using particle theory, why:
a) a hot air balloon floats on air
(4)
b) a bicycle tire that is overfilled with air can blow up
c) a balloon will expand if heated
1) Decide whether the following are pure substances, solutions or mechanical mixtures:
a) water _________________________ b) salt water _________________________
c) rocky road ice cream _________________________
(4)
d) steel _________________________ e) air ____________________________
f) fizzy gingerale ______________________ g) clear glass _____________________
h) oil and vinegar salad dressing _________________________
2) Rewrite the following FALSE or INCOMPLETE statements to make them true.
a) Elements are made of compounds.
(3)
b) H2 is an atom of an element.
c) A compound is a particle made of two or more atoms.
3) Fill in the following chart:
Substance
hydrogen gas
carbon dioxide
methane gas
silver
(8)
Element or Compound?
Atom or Molecule?