compounds have atoms from more than one element
atoms can bond together to make molecules
all helium atoms have one more proton than all hydrogen atoms
all oxygen molecules have 8 neutrons
an irrational number is one that cannot be expressed as the ratio of integers
fractions equal to 1 are called mixed fractions
the numerator is less than the denominator in a proper fraction
a composite number is a positive integer greater than 1 that is not prime
every real number has a reciprocal
the product of two integers is always positive
the quotient times the divisor equals the dividend
the product of two numbers is greater than either factor
the boiling point of water decreases with increased altitude on Earth
the melting point of table salt is much higher than that of glucose
radon is radioactive
metals react with nonmetals to form new metals
a line that intersects 2 other lines at different points is called a transversal
if a ≤ 0 (read as: if a is less than or equal to 0), then the absolute value of a equals a
the square of an integer is called a perfect square
the real numbers include all rational and irrational numbers
the largest angle in a right triangle is 90º
each side of a regular polygon has the same length
the side opposite an obtuse angle is the shortest side of a triangle
a triangle can have only 1 obtuse angle
all tropical depressions form into tropical storms
the Intertropical Convergence Zone is mostly located near the equator
most hurricanes originate along the equator
all hurricanes have a counterclockwise motion
the freezing point of pure water is 0ºC at sea level
when pure water freezes, it reaches its maximum density at 0ºC
adding salt to ice will lower its melting point
when pure maple syrup is cooled below 0ºC, pure water ice separates out
global sea levels have generally risen over the past 18,000 years
the Mississippi River Delta in Louisiana has one of the highest rates of wetland loss in the U.S.
tide stations measure local sea levels
most of Earth’s groundwater comes from glacial meltwater
all fires burn with a yellow flame
snowflakes and raindrops often contain bacteria
a general rule for solubility is that ‘like dissolves like’
a super-cooled liquid is a liquid at a temperature below its normal freezing point
all yeasts are nonpathogenic in humans
all humans have the same number of chromosomes
all bats carry rabies
all DNA contains phosphorous
all living things require energy except in some states of dormancy
energy is transformed from one state to another in living things
the laws of thermodynamics do not apply to living things
enzymes allow certain reactions to occur at faster rates than without them
π is an irrational number
a dodecahedron has 12 faces
5 factorial is 5-times as large as 4 factorial
if n is a multiple of 2, then n + 1 is also a multiple of 2
unlike charges repel
lithium is an alkaline earth metal
magnetic poles always come in pairs
some isotopes of helium have 1 proton
all natural numbers are whole numbers
all whole numbers are integers
all integers are rational numbers
all numbers can be both a rational number and an irrational number
all the DNA in a eukaryotic cell is contained in the nucleus
chiasma are a method of genetic interchromasomal exchange
in deuterostomes, the blastopore forms the anus
in lower plants the sporophyte is parasitic upon the gametophyte
sound waves can be considered longitudinal waves
light slows down when it enters glass from dry air
as a light wave’s frequency increases so must its amplitude
light can be produced with one frequency
pyroclastic flows dominate Hawaiian volcanoes
granitic magma contains less silica than basaltic magma
peridotite is rock found within the Earth’s mantle and some meteorites
plutons are large masses of basalt
the temperature of a substance changes during a phase change
a compound can be broken down by chemical means
some known elements are unstable and only last for fractions of seconds
the opposite of vaporization is condensation
neutral pH solutions have small but equal numbers of hydronium and hydroxide ions
when an acid is added to water it will increase the solutions concentration of hydronium ions
strong acids dissociate almost completely in water
strong bases do not dissociate in water
weight decreases as you move away from the Earth’s surface
mass times gravitational acceleration is weight
gravitational potential energy increases with increasing height
kinetic energy can only decrease when potential energy decreases
23 – 3 × 2 = 17
72 ÷ 9 – 3 = 5
0.3 + 0.4 × 2 = 1.4
6 + 6 × 2 = 18
two numbers are reciprocals if their product is 1
one-half of three quarters is three eighths
a whole number is divisible by 5 if the ‘ones’ digit is 0 or 5
an example of a proper fraction is 4 6
5 × 0 = 0
2 × ½ = 5 ÷ 5
0 5 0 =
5 0 5 =
30% × 60% = 18%
the square of an odd number is always odd
the reciprocal of the smallest prime number is ½
the number 27 is a perfect square
the Milky Way is an elliptical galaxy
our Sun will become a red giant in the far distant future
constellations are patterns of stars in the night sky
the average sunspot cycle is 11 years
yeast reproduces asexually
lichens are the mainstay of the caribou diet
coal is not a native mineral
a spider’s web is made from a specialized carbohydrate
when diluting strong acids, it is safer to pour the acid into the water
carbon monoxide is a poisonous gas
iron plays a central role in the chlorophyll molecule
the pH of soapy water is basic
a robotic spacecraft recently landed on the surface of a near-Earth asteroid
a team of researchers plan to build a neutrino observatory at the bottom of the Mediterranean Sea
skin cancer is becoming more common and appearing at younger ages
solar activity is currently at an 11-year cyclical high point
all natural numbers are whole numbers
all whole numbers are integers
all integers are rational numbers
all numbers can be both a rational number and an irrational number
all the DNA in a eukaryotic cell is contained in the nucleus
chiasma are a method of genetic interchromasomal exchange
in deuterostomes, the blastopore forms the anus
in lower plants the sporophyte is parasitic upon the gametophyte