Earth Science Vocab - 9th Grade Midterms

Scientific Method

A series of steps followed to solve problems including collecting data, formulating a hypothesis, testing the hypothesis, and stating conclusions.

Testable Question

can be answered by designing and conducting an experiment

untestable question

can not be tested experimentally to find the answer if it even has one

independent variable

variable that is manipulated (x)

dependent variable

a variable whose value depends on that of another. (y)

Hypothesis

A testable prediction, often implied by a theory

Observation

Information obtained through the senses.

Inference

A conclusion reached on the basis of evidence and reasoning

quantitative data

Data associated with mathematical models and statistical techniques used to analyze spatial location and association.

qualitative data

descriptive data

percent error

the absolute value of the error divided by the accepted value, multiplied by 100%

controlled experiment

An experiment in which only one variable is manipulated at a time.

constant

A value that does not change

control

standard for comparison

Atom

Basic unit of matter

Nucleus

Control center of the cell

Proton

A subatomic particle that has a positive charge and that is found in the nucleus of an atom

Neutron

A subatomic particle that has no charge and that is found in the nucleus of an atom

electron cloud

a region around the nucleus of an atom where electrons are likely to be found

Electron

A subatomic particle that has a negative charge

valence electrons

Electrons on the outermost energy level of an atom

Ion

A charged atom

mass

the amount of matter in an object

pure substance

A sample of matter, either a single element or a single compound, that has definite chemical and physical properties

element

A substance that cannot be broken down into simpler substances

diatomic element

element whose atoms can form covalent bonds with another atom of the same element

Molecule

two or more atoms held together by covalent bonds

compound

A substance made up of atoms of two or more different elements joined by chemical bonds

Coefficient

A number in front of a chemical formula in an equation that indicates how many molecules or atoms of each reactant and product are involved in a reaction.

chemical formula

A combination of chemical symbols and numbers to represent a substance

Mixture

A combination of two or more substances that are not chemically combined

homogeneous mixture

A mixture in which substances are evenly distributed throughout the mixture

Solution

A homogeneous mixture of two or more substances

heterogenous mixture

a mixture in which the composition is not uniform throughout

Suspension

A mixture in which particles can be seen and easily separated by settling or filtration

Colloid

A mixture containing small, undissolved particles that do not settle out.

Tyndall effect

Scattering of a light beam as it passes through a colloid

System

A group of parts that work together as a whole

day

the time required for Earth to rotate once on its axis

year

the time required for the Earth to orbit once around the sun

Biosphere

part of Earth in which life exists including land, water, and air or atmosphere

geosphere

the solid part of the earth consisting of the crust and outer mantle

Hydrosphere

All the water at and near the surface of the earth, 97% of which is in oceans

Salinity

A measure of the amount of dissolved salts in a given amount of liquid

polar molecule

molecule with an unequal distribution of charge, resulting in the molecule having a positive end and a negative end

nonpolar molecule

molecule that shares electrons equally and does not have oppositely charged ends

Disassociation

a split in consciousness, which allows some thoughts and behaviors to occur simultaneously with others

atmosphere

A mixture of gases that surrounds a planet or moon.

pressure

the amount of force exerted per unit area of a surface

direct relationship

a relationship in which one variable increases with an increase in another variable

inverse relationship

a relationship in which one variable decreases when another variable increases

oceanic crust

the portion of Earth's crust that is usually below the oceans and not associated with continental areas, thinner and higher in density that continental crust and basaltic rather than granitic in composition

basalt

A dark, dense, igneous rock with a fine texture, found in oceanic crust

continental crust

The portion of the earth's crust that primarily contains granite, is less dense than oceanic crust, and is 20-50 km thick. Made of granite and magnesium

Granite

A usually light colored igneous rock that is found in continental crust

mantle

The layer of hot, solid material between Earth's crust and core.

Asthenosphere

the upper layer of the earth's mantle, below the lithosphere, in which there is relatively low resistance to plastic flow and convection is thought to occur.

Lithosphere

the solid, outer layer of the earth that consists of the crust and the rigid upper part of the mantle

outer core

the liquid layer of the Earth's core that lies beneath the mantle and surrounds the inner core. iron and nickel

inner core

A dense sphere of solid iron and nickel at the center of Earth

Thermodynamics

The study of energy transformations that occur in a collection of matter.

thermal energy

The total energy of motion in the particles of a substance

heat

The energy transferred between objects that are at different temperatures

heat transfer

the movement of energy from a warmer object to a cooler object

radiation

Energy that is radiated or transmitted in the form of rays or waves or particles.

conduction

The direct transfer of heat from one substance to another substance that it is touching.

Convection

Process by which, in a fluid being heated, the warmer part of the mass will rise and the cooler portions will sink.

fluid

A substance that flows

density

the degree of compactness of a substance. Mass per unit volume

convection current

the movement of a fluid, caused by differences in temperature and density, that transfers heat from one part of the fluid to another. warm material (less dense) rises, while cold material (more dense), sinks.

Hypothesis

A testable prediction, often implied by a theory

continental drift

The hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations

pangea

A supercontinent containing all of Earth's land that existed about 225 million years ago.

theory

A hypothesis that has been tested with a significant amount of data

Fossil

A trace of an ancient organism that has been preserved in rock.

mid-ocean ridge

An underwater moutain chain where new ocean floor is formed

sea-floor spreading

The process by which molten material adds new oceanic crust to the ocean floor

Subduction

The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary.

ocean trench

Deep valley in the ocean floor that forms along a subduction zone

plate tectonics

The theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle.

divergent boundary

A plate boundary where two plates move away from each other.

convergent boundary

A plate boundary where two plates move toward each other.

transform boundary

A plate boundary where two plates move past each other in opposite directions

Hydrocarbons

Compounds composed of only carbon and hydrogen

Combustion

A rapid reaction between oxygen and fuel that results in fire. the process of burning something.

Group

a vertical column of elements in the periodic table

period

A horizontal row of elements in the periodic table

Bohr Model

model of the atom in which electrons move rapidly around the nucleus in paths called orbits

octet rule

States that atoms lose, gain or share electrons in order to acquire a full set of eight valence electrons

Lines Of Latitude

Imaginary lines that run east and west across the earth

equator

An imaginary circle around the middle of the earth, halfway between the North Pole and the South Pole. 0 degrees latitude

lines of longitude

Imaginary lines that run north and south across the earth

Prime Meridian

The meridian, designated at 0° longitude, which passes through the Royal Observatory at Greenwich, England.

volcano

A vent or fissure in the Earth's surface through which magma and gases are expelled. a mountain or hill, typically conical, having a crater or vent through which lava, rock fragments, hot vapor, and gas are being or have been erupted from the earth's crust.

magma

A molten mixture of rock-forming substances, gases, and water from the mantle

lava

Liquid magma that reaches the surface; also the rock formed when liquid lava hardens.

igneous rock

a type of rock that forms from the cooling of molten rock at or below the surface

Basalt

A dark, dense, igneous rock with a fine texture, found in oceanic crust

volcanic island arc

a chain of volcanic islands generally located a few hundred kilometers from a trench where there is active subduction of one oceanic plate beneath another

Ring of Fire

A major belt of volcanoes that rims the Pacific Ocean