chap 2 - matter and atomic structure Flashcards
what is the changes in state of matter caused by?
it is caused by heating or cooling
what is solid to liquid called
melting
what is liquid to gas called
boiling
evaporation
what is gas to liquid called
condensation
what is liquid to solid called
freezing
what is solid to gas called
sublimation
what is gas to solid called
deposition
explain the state of matter in solid (3m)
- particles are closely packed
- kinetic energy of particles is low
- attraction force between particles is strong
explain the state of matter in liquid (3m)
- particles are closely packed but not in an orderly manner
- kinetic energy is high than solid state
- attraction force between particles is strong but less than solid
explain the state of matter in gas (3m)
- particles are far apart
- kinetic energy of particles are very high
- attraction force between particles is weak
state two types of matter
element
compound
state two classification of elements
atom
molecule
state two classification of compound
molecule
ion
what is melting point
is the constant temperature when a substance changes from solid to liquid at a specific pressure
what is freezing point
is the constant temperature when a substance changes from liquid to solid at a specific pressure
in the heating of naphthalene,, why is it not heated directly?
to avoid naphthalene from sublimating and producing poisonous gas
in the heating of naphthalene, why is a water bath used
to ensure even heating
is the cooling of naphthalene,, why is the boiling tube put in a conical flask
to ensure even cooling
in the cooling of naphthalene , why is it stirred continuously
to ensure even cooling
in cooling of naphthalene, what happens if naphthalene is not stirred continuously
supercooling will occur
why is the temperature constant when melting occurs
no increase in temperature because heat energy absorbed by the particles is used to overcome the attraction force between the particles until solid changes to liquid
why is the temperature constant when freezing occurs
no decrease in temperature because heatenergy that is lost to the surroundings is balanced by the heat energy released when the particles attract each other to form solid
what was john dalton’s discovery in the development of the atomic structure model
matter is made out of atoms
atom is the smallest substance
same elements same atoms
what was JJ thomson discovery in the development of the atomic structure model
there are electrons
atom is positively charged with electrons in it
