1. Carbon Monoxide
   Carbon Dioxide
2. Sulfuric Acid
   Calcium Dioxide

C is the abbreviation for carbon while O stands for oxygen. Two molecules of oxygen attached to the carbon would make the compound carbon dioxide.

1. Panther
   Cheetah
2. Jaguar
   Leopard

While the animals listed all run very quickly, the cheetah is the fastest running land animal. Some cheetahs can run up to 75 mph!

1. A
   B
2. C
   AB

There are 4 blood types: A, B, AB, and O.

1. NaAlO2
   HCl3
2. NaCl
   H2SO4

Table salt is made from the combination of the elements sodium and chlorine. They form the compound NaCl, which is commonly called sodium chloride.

1. 1
   2
2. 3
   4

The Earth has four layers, going from the most superficial layer to the interior: crust, mantle, outer core, and inner core.

1. Phylum
   Class
2. Kingdom
   Order

When it comes to animals and ranking them, it goes from broad to more specific: domain, kingdom, phylum, class, order, family, genus, and species.

1. Virgo
   Capricorn
2. Aquarius
   Volvella

There are 12 signs of the zodiac that have been spread throughout a calendar year. The zodiac begins at zero degrees longitude, with Aries as the starting point.

1. A
   B
2. AB
   O

When it comes to donating blood, those with the blood type O are always in high demand. This blood type is known for being the universal donor and can give blood to those with the remaining types.

1. 100
   165
2. 187
   206

The 'average' adult human body is made up of 206 bones. This number decreases from birth. Babies are born with around 300 bones that have yet to fuse together.

1. A
   B
2. C
   D

The Sun is known for producing vitamin D within the body. When the skin is exposed, it is able to produce an ​excess of the vitamin. Vitamin D also helps with the absorption of calcium, which is crucial to healthy bones.

1. 1
   10
2. 100
   1000

When it comes to grams and milligrams, you'd need 1000 milligrams just to form one gram, so you'll only find 1 gram in 1000 milligrams.

1. 0
   32
2. 50
   100

Zero degrees Celsius is the freezing marker for that unit, while 32 degrees Fahrenheit is the equivalent freezing temperature.

1. Isaac Newton
   Louis Pasteur
2. Charles Darwin
   Galileo Galilei

Charles Darwin was well known for this theories on evolution as well as his book "On the Origin of Species" and his thoughts on mutations and natural selection.

1. 1
   4
2. 7
   11

The pH scale ranger from 1-14, the lower being acidic and the higher being basic, or alkaline. Pure water is completely neutral, falling at 7. You'll find soda and wine ranging from 3-5 and substances like ammonia and bleach ranging from 11 and above.

1. Fall Equinox
   Summer Solstice
2. Spring Equinox
   Winter Solstice

The Summer Solstice, which always falls on June 21, is the longest day of the year. This day, which signifies the beginning of summer, happens when the sun is above the Tropic of Cancer. It is deemed the longest day of the year because it is the day with the most sunlight.

1. Salt
   Sugar
2. Pepper
   None of the above

When something is soluble in water, it means it has the ability to dissolve. Sugar and salt are both able to dissolve in water while pepper cannot, meaning it is insoluble.

1. Lithium
   Chromium
2. Tin
   Xenon

A great way to remember SOME of the metals is that many of them end in -ium. Lithium is an Alkali metal while Chromium is a transition metal. Tin, an exception to the -ium rule, is a poor metal, and Xenon, the answer to this question, is a noble gas.

1. A
   B
2. AB
   There is no universal receiver.

Blood type 'AB' is known for being the universal receiver in the medical world. Since they have both blood types A and B, they can receive both samples, while also being able to receive from the universal donor, O.

1. Carbon Monoxide
   Ammonium Hydroxide
2. Nitrous Oxide
   Hydrogen Sulfide

If you've ever had a major procedure done at the dentist's office, they might have given you nitrous oxide to knock you out. Its chemical formula is N2O.

1. Hertz
   Kelvin
2. Fahrenheit
   Celsius

Hertz is a unit used for frequency, while the remaining three are used for temperature. Kelvin is considered the absolute scale where 0 Kelvin is equivalent to -273.15 degrees Celsius.

1. Alkaline Earth Metals
   Transition Metals
2. Halogens
   Noble Gases

The halogens on the periodic table can be found in group VIIA. There are 5 elements included in the list of halogens. They are fluorine, chlorine, bromine, iodine, and astatine.

1. Glucose
   Lactose
2. Sucrose
   Fructose

While all of the options are sugar, sucrose is used as table sugar. Glucose is commonly referred to as blood sugar, lactose is milk sugar, and fructose is found in plants, fruits, flowers, and vegetables.

1. 3
   4
2. 5
   6

Humans are said to have 5 basic tastes. The obvious ones are salty, sweet, sour, and bitter. The last one is umami, which is used to explain the states of amino acids.

1. 9.8 m/s^2
   3.7 m/s^2
2. 1.3 m/s^2
   8.9 m/s^2

The magnitude of gravity is different on every surface of the solar system. While the gravity on the moon is 1.6 m/s^2, the gravity on Earth is 9.8 m/s^2.

1. Pluto
   Saturn
2. Neptune
   Jupiter

If you said Pluto, you're definitely wrong! Pluto is no longer a full planet in our solar system. Neptune is now the furthest planet from the sun.

1. Chickenpox
   Measles
2. Polio
   Tuberculosis

Jonas Salk is the researcher who is credited with creating the polio vaccine that was introduced to the world in 1955 after the massive outbreaks in the early 1950s.

1. Evaporation
   Condensation
2. Sublimation
   Melting

Evaporation is when a liquid goes into the gas state. Condensation is when a gas phases into a liquid. Melting is when a solid turns to a liquid, but sublimation is when a solid completely skips the melting phase and turns straight into a gas.

1. Hydrogen
   Oxygen
2. Potassium
   Zinc

As the number increases on the period table, the higher the atomic mass. Hydrodgen, the first element on the table, has the smallest atomic mass at 1. Zinc, which comes in at element 30, has an atomic mass of 65.38.

1. Protons only
   Electrons only
2. Protons and neutrons
   Protons and electrons

Atomic mass is determined by the number of protons and neutrons that an element has. For example, carbon has an atomic mass of 12. Six of these are because it has 6 protons (given by atomic number), and since its mass is 12, the remaining amount is attributed to its number of neutrons.

1. Height
   Time
2. Light
   Distance

While you might think light-years are used to measure light or time, it's actually used to describe distance in outer space.

1. Stratus
   Cirrus
2. Cirrocumulus
   Sirius

Sirius is not a type of cloud you'll find in any sky. The more common clouds are stratus, cumulus, and cirrus. Prefixes such as alto, cirro, and nimbo are added to determine the level in which they are found in the sky.

1. Alfred Nobel
   Albert Einstein
2. Dmitri Mendeleev
   Isaac Newton

Isaac Newton is the only scientist listed who doesn't have an element named after him. Alfred Nobel, the inventor of dynamite, has element 102 named after him, while element 99, Einsteinium, was named after Albert Einstein. Element 101 was named after Dmitri Mendeleev, who is known as the father of the periodic table.

1. 1
   365
2. 12
   2

Don't get your rotations and revolutions confused! The Earth rotates about 365 times a year, but it revolves around the Sun once every year!

1. 3
   4
2. 5
   6

There are four chambers of the heart that are each responsible with pumping oxygenated or deoxygenated blood within the body. The four chambers are: left and right atriums and left and right ventricles.

1. Solid
   Liquid
2. Gas
   None of the above

When it comes to room temperature, most of the elements would be in solid form. As the temperature increases, some of them would melt down to liquids or form into a gas.