3.1.1 introduction Flashcards
physical changes create __ ___ __________
no new substances
physical changes are usually ____ to reverse
easy
physical changes absorb or release small amounts of ______
energy
what is the chemical test for water
anhydrous copper (II) sulphate
anhydrous copper (II) sulphate turns from
white to blue if water is present
the melting point for pure water is near
0 degrees
the boiling point for pure water is near
100 degrees
metal properties include
high melting and boiling points
electrical conductors
malleable
shiny
non-metal properties include
low melting and boiling points
electrical insulators
brittle
dull
metals are on the ____ side on the periodic table
left
non-metals are on the _____ hand side of the periodic table
right
chemical changes create ___ __________
new substances
chemical changes are usually _________ to reverse
difficult
chemical changes absorb or release large amounts of ______
energy
a good example of a physical change is
ice melting in a beaker
a good example of a chemical change is
burning wood on the floor
when ice is melted in a beaker the particles are still _____ particles
water
you can reverse ice is melted in a beaker by
putting the water in the freezer
when ice is melted in a beaker the beaker does not get much
hotter or colder
when wood is burnt on the floor the wood & oxygen particles turn into
soot & ash
when wood is burnt on the floor it is impossible to collect the ____ & ___ and turn it
soot & ash
back into wood
when wood is burnt on the floor the floor gets
really hot
physical changes absorb or release _____ amounts of energy
small
chemical changes absorb or release _____ amounts of energy
large
describe what happens when a substance melts
• the particles gain kinetic energy
• they vibrate faster
until they have energy to break
the forces holding them together
• they move past eachother
why does water evaporate faster at a higher temperature
• the kinetic energy of the particles
increase
• more particles have enough energy
to break the forces holding them
together
solid movement
regular arrangement
vibrating in fixed position
liquid movement
random and close
move past eachother
gas movement
random and far apart
randomly moving at very high speeds
solid to gas is
deposition
gas to solid is
sublimation
solid to liquid is
melting
liquid to solid is
freezing
liquid to gas is
boiling
had to liquid is
condensing
when a solid turns into a liquid
the particles vibrate more and gain heat energy
they then can overcome some of the bonds that kept them in fixed position
they can move around and the solid becomes a liquid
