Grade 6

Question Answer
What are the two major ways the Earth moves through space? Rotation and revolution
Why does Earth have seasons? Its axis is tilted as it revolves around the sun
What two factors does the strength of the force of gravity between two objects depend on? Masses of the objects and the distance between them
What did Newton conclude about the two factors-inertia and gravity- combined do? Keep Earth in orbit around the sun and the moon in orbit around Earth
What does the changing relative positions of the moon, Earth, and sun cause? The phases of the moon, eclipses, and tides
What do the phases of the moon you see depend on? How much of the sunlit side of the moon faces Earth
When does an eclipse occur? When the moon's shadow hits Earth or Earth's shadow hits the moon
When does a solar eclipse occur? When the moon passes directly between Earth and the sun, blocking sunlight from Earth
What happens during a lunar eclipse? Earth blocks sunlight from reaching the moon
What causes tides? Tides are caused mainly by differences in how much the moon's gravity pulls on different parts of Earth
What are the features of the moon's surface? Maria, Craters, and Highlands
Compare the moon and the Earth with their sizes and surface gravity Moon is dry and airless. Moon is 1/4 diameter of Earth and 1/80 of Earth's mass. Earth has a stronger gravitational pull because of the difference in mass (Earth=more mass)
What do scientists theorize about how the moon formed? A planet – sized object collided with Earth to form the moon. Then material from the object and Earth's outer layer was ejected into orbit around Earth, where it formed a ring. Gravity then caused the material to combine and form a moon
What are solstices and equinoxes? How are they related to the seasons? They are both changes in the seasons. They are related to the seasons because they mark the beginning of each season
Suppose the moon were closer to Earth. How would the force of gravity between Earth and the moon be different? The force of gravity would increase and be stronger. The tides would be larger too.
How would Earth move if the sun (including gravity) suddenly disappeared? Inertia would cause the Earth to travel in a straight line.
How is a solar eclipse different from a lunar eclipse? Solar: Occurs when the moon passes directly between the Earth and the sun, blocking sun from Earth
Lunar: Earth blocks sun from reaching the moon
What causes the difference in tides? Tides are mainly caused by differences in how much the moon's gravity pulls on different parts of Earth.
Why is the moon's surface more heavily cratered than Earth's surface? Earth's craters have worn away over time by water, wind, and other forces
Why is it less likely to see a total solar eclipse than a total lunar eclipse? The moon's umbra only covers a small area on Earth's surface
What do scientists call the theory on how the moon was formed? Collision – Ring Theory
Lunar Eclipse The blocking of sunlight to the moon that occurs when Earth is directly between the sun and moon
Solar Eclipse The blocking of sunlight to Earth that occurs when the moon is directly between the sun and Earth
Spring Tide The tide with the greatest difference between consecutive low and high tides
Neap Tide The tide with the least distance between consecutive low and high tides
Weight The force of gravity on an object
Mass The amount of matter in an object
Law of Universal Gravitation Newton's law that states that every object in the universe attracts every other object
Tide The periodic rise and fall of the level of water in the ocean
Umbra The very darkest part of the moon's shadow
Astronomy The study of the moon, stars, and other objects in space
Equinox The 2 days of the year on which neither hemisphere is tilted toward or away from the sun
Penumbra The part of a shadow surrounding the darkest part
Eclipse When an object in space comes between the sun and a third object, it casts a shadow on that object
Gravity A force that attracts all objects toward each other
Phases The different shapes of the moon you see from Earth
Calendar A system of organizing time that defines the beginning, length, and divisions of a year
Force A push or a pull
Revolution The movement of one object around another
Newton's First Law of Motion A scientific law that says that an object at rest will stay at rest and an object in motion will stay in motion with a constant speed and direction unless acted on by a force
Rotation The spinning of Earth on its axis
Axis The imaginary line that passes through Earth's center and the north and south poles
Orbit The path of an object as it revolves around another object in space
Inertia The tendency of an object to resist a change in motion
Solstice Each of these days when the sun is farthest north or south of the equator

Lesson 3 Characteristics of stars

Term Definition
Spectrograph an instrument that separates light into colors and makes an image of the resulting spectrum
Apparent Brightness the brightness of a star as seen from Earth
Absolute Brightness the brightness a star would have if it were at a standard distance from Earth
Hertzsprung-Russell Diagram a graph relating the surface temperatures and absolute brightness of stars
Main Sequence a diagonal area on a Hertzsprung-Russell diagram that includes more than 90% of all stars

Lesson 4 Lives of Stars

Term Definition
Nebula a large cloud of gas and dust in space
Protostar a contracting cloud of gas and dust with enough mass to form a star
White Dwarf the blue-white hot core of a star that is left behind after its outer layers have expanded and drifted out into space
Supernova the brilliant explosion of a dying super giant star
Neutron Star the small, dense remains of a high-mass star after a supernova
Pulsar a rapidly spinning neutron star that produces radio waves
Black Hole an object whose gravity is so strong that nothing, not even light, can escape

Chapter 9 vocabulary using book definitions

Term Definition
mass the amount of matter in an object
weight how strongly gravity pulls on an object
volume how much space matter takes up
matter anything that has mass and volume
density the amount of mass for each cubic centimeter of a substance
buoyancy resistance to sinking
element a material that cannot be broken into anything simpler by chemical reactions
metal elements that share the common properties of luster, conductivity, and flexibility
atom the smallest unit of an element that still retains the properties of that element
nucleus the center of an atom
proton a particle with one unit of positive charge each
neutron a particle with no electric charge – it is neutral
electron smaller particles with one unit of negative charge each
molecule particles with more than one atom joined together
malleability the ability to be bent, flattened, or hammered without breaking
ductility the ability to be pulled into thin wires without breaking
corrosion when metals combine with nonmetals from the environment
semiconductor a material that conducts electricity better than a nonmetal, but not as well as a metal

Vocabulary with alternative definitions

Term Definition
Mass the stuff objects are made of
volume space that objects take up
weight gravity acting on mass
matter a thing with mass & volume
density mass over volume
buoyancy floating
element the most basic matter
metals shiny, pretty things are made of these types of elements
atoms the smallest pieces of matter
nucleus where the protons and neutrons are
proton positive particle in the middle of atoms
neutron neutral particle in the middle of atoms
electrons negative particle on the outside of atoms
molecules groups of atoms
malleability poundability
ductility stretchability
corrosion metals rotting away
semiconductor kind of able to move electricity. sometimes.
luster shiny-ness

Questions and answers

Question Answer
Which unit is used to measure weight? newtons or pounds
What is used to measure mass? grams or kilograms
What unit is used to measure volume? mL or cm3
What is the formula for density? mass divided by volume
What property depends on shape, volume, or mass? buoyancy
What state of matter has a definite shape? solid
Which states of matter have a definite volume? liquids and solids
How strongly gravity pulls on an objects mass is _________. weight
What does it mean to say that an element is more "reactive"? it is likely to combine with lots of elements
If an object displaces 20 mL of water, what is that object's volume? 20 mL
Which state of matter has molecules that move the fastest? gas
Which state of matter has molecules that move the slowest? solids
What shape are liquid molecules? The shape of the container they're in.
What shape are gas molecules? The shape of the container they're in.
What shape are solid molecules? Trick question! They can make all the shapes!
How many electrons in a carbon atom? 6
How many protons in an oxygen atom? 8
How many neutrons in a calcium atom? 20
What are the four properties of metals? Luster, malleability, ductility, and conductivity
Where are the metals on the periodic table? On the left and in the middle.
Where are the nonmetals on the periodic table? On the right.
Where are the metalloids on the periodic table? Between the metals and the nonmetals.
Which elements on the periodic table are the most similar? The ones in the same column.
Where are the noble gases on the periodic table? In the far right column
Why are the noble gases called noble? Because they don't mix with the other elements – like kings and queens don't hang out with commoners!
What do you do if you don't know the answer to a question? Mark it! Skip it! Come back to it later!
What can you do if you don't know the answers to the questions at the very end of the test? Look for clues in other questions. Guess. Draw yourself a picture to help figure it out. Don't worry! It's just a test!
What's the most important thing you can study late at night before the test? Your pillow! Sleep is just as important as studying!

Book definitions of vocabulary from chapter 10, lessons one and two

Term Definition
physical change alters the form of a substance without changing what type of matter it is.
sublimation the change in state directly from solid to gas
melting point the temperature at which a substance melts
boiling point the temperature at which a substance boils
freezing point the temperature at which something freezes
thermal expansion the increase in an object's volume due to a change in heat
thermal contraction the decrease in an objects volume due to a change in heat
mixture a physical combination of substances
colloid a mixture like a suspension, except its sat_flash_1s do not settle
solution a mixture with parts that blend so that it looks the same everywhere, even under a microscope
solute the smaller amount that is dissolved in a solution
solvent the larger amount that dissolves the other substance in a solution
alloy a solution of metal and another solid
solubility the maximum amount of a solute that can dissolve in a solvent
distillation the process of separating liquids by evaporation and condensation

paraphrased definitions from chapter 10, lessons one and two

Term Definition
physical change change in shape, but not type
sublimation solid to gas
melting point moment of solid to liquid
boiling point moment of liquid to gas
freezing point liquid to solid
thermal expansion get hotter, get bigger.
thermal contraction get colder, get smaller.
mixture physical combine
colloid non-settling mixture
solution perfectly blended mixture
solute gets dissolved
solvent does the dissolving
alloy metal solution
solubility how much can dissolve
distillation evaporate to separate

Questions and answers from chapter 10, lessons one and two

Question Answer
how could snow disappear without making a puddle? sublimation!
does a gas gain heat when it condenses? no – condensation comes with cooling
what might happen if there were no spaces between sections of a sidewalk? the sidewalk would break from thermal expansion and contraction
the temperature at which a substance melts is called its __________ melting point
why wouldn't turning up the heat on the stove make boiling water cook things faster? because liquid water can't get hotter than it is when it's boiling!
what kind of mixture is dusty air? it's a suspension
what might happen if you mixed two suspensions? you might get four layers!
how can you tell muddy water isn't a colloid? because the dirt eventually settles to the bottom
why might fish not get enough oxygen in hot water? because hot water can't hold as much dissolved oxygen as cold water
if two liquids boil at about the same temperature, would it be easy to separate them by distillation? no, because it would be too easy to boil them both away at the same time!
a solution of metal is called an ___________ alloy
a solution of sugar in water has a solubility limit. Do heterogenous mixtures have solubility limits? nope- you can just make that mixture more chunky – like Ben & Jerry's Ice Cream!
How can matter change state? by gaining or losing energy!
what happens to the temperature when matter is changing state? the temperature stays the same

Lesson 5 Star Systems and Galaxies

Term Definition
Binary star A star system with two stars
Eclipsing Binary a binary star system in which one star periodically blocks the light from the other
Open Cluster a star cluster that has a loose, disorganized appearance and contains no more than a few thousand stars
Globular cluster a large, round, densely-packed grouping of older stars
Galaxy a huge group of single stars, star systems, star clusters, dust, and gas bound together by gravity
Spiral galaxy a galaxy with a bulge in the middle and arms that spiral outward in a pinwheel pattern
Elliptical galaxy a galaxy shaped like a round or flattened ball, generally containing only old stars
Irregular galaxy a galaxy that does not have a regular shape
Quaear an enormously bright, distant galaxy with a giant black hole at its center