chemistry amd physics
gap fill: light cannot travel through .................... materials
opaque
a light wave is also known as a
ray
which colours of loght are reflected by a white object?
all of them
what is wave length meassured in?
metres
unit for frequency
heartz
any sound wave with a frequency above 20000 heartz this is a frequency above hjman hearing
what am I?
ultrasound
what is a hazard?
something that can cause harm
what is a risk?
the chance that any hazard will actually cause someone harm
what equation is this? acid + alkali -> salt + water
neutralisation
gap fill: ....................... reactions transfer energy out through an exit
exothermic
gap fill: ................... reactions transfer energy in you go in through an entrance
endothermic
solid to a gas is called
sublimation
CH4 is
methane
a substance that burns to transfer energy is called
fuel
hydrogen + oxygen =
water
solid to liquid
melting
liquid to solid
freezing
liquid to gas
evaporating
gas to liquid
condesating
solid to gas
deposition
a substance's form changes but not the substance itself is a
a physical change
changes the substance into a new substance is a
chemical change
oscilation is when
something moves back and forth repeatidly between 2 positions
the lowest point of a wave is called a
trough