NOUN
The Earth’s ________ contains gases such as oxygen and nitrogen.
atmosphere
When water boils at 100°C, it changes into ________.
steam
When you take a deep breath before running, you ________ oxygen to supply your muscles.
inhale
________ combines with oxygen to form water.
Hydrogen
The ozone ________ protects the Earth from harmful radiation.
layer
A ________ is commonly used to measure changes in air pressure.
barometer
Smoke is made up of extremely small ________ that move freely in the air.
particle
Chocolate left in the sun will start to ________.
melt
Water can change its ________ when it freezes, melts, or boils.
state
Plants absorb ________ during photosynthesis.
carbon dioxide
Ice is ________ because it has a fixed shape and volume.
solid
Oxygen is a ________ that spreads out to fill its container.
gas
When left in the sun, a puddle of water will slowly ________.
evaporate
Microorganisms can ________ in places with very little water, like deserts.
exist
Atoms are extremely ________ and cannot be seen without special equipment.
tiny
Beyond the Earth’s atmosphere, ________ contains almost no air.
space
Anything that has mass and occupies space is called ________.
matter
Fog can ________ a city in the morning, making it hard to see far.
surround
When you spray perfume in a room, the scent molecules quickly ________ the air throughout the room.
occupy
Air is ________ nitrogen, oxygen, and other gases.
composed of
Air pressure is highest at ________ and lower on mountains.
sea level
Sound cannot travel in a ________ because there are no particles.
vacuum
The kettle ________ water into steam when heated.
converts
A sandwich can ________ bread, cheese, vegetables, and a little bit of imagination.
consist of
Metals ________ when they are heated, which can make bridges or rails longer.
expand