Science unit 2 vocab

compound

a substance that is composed of two or more separate elements; a mixture.

Matter

Anything that has mass and takes up space

element

A substance that cannot be broken down into simpler substances

atom

the basic unit of a chemical element.

isotope

same number of protons but a different number of neutrons

molecule

Two or more atoms of the same or different elements held together by covalent chemical bonds

ion

Gain or lose electrons and form a positive or negative charge

Form ionic compounds

a compound that is formed by ionic bonding

ionic bond

between metals and nonmetals, Transfer of electrons from one atom to another

covalent bond

electrons shared between two atoms, valence electrons shared with another atom to form a stable structure

pH

level of the acidity or basicity

pH scale

A measure of how acidic or basic a substance or solution is

Acid

any hydrogen-containing substance that is capable of donating a proton (hydrogen ion) to another substance

Base

a substance that can accept hydrogen ions in water and can neutralize an acid

neutral

An object is neutral when it is not positively or negatively charged

Neutralization reaction

a reaction of an acid and a base that results in an ionic compound and possibly water

hydrogen ion

a positively charged molecule

hydroxide ion

A negatively charged ion made of oxygen and hydrogen.

inorganic compound

A compound that does not contain carbon

organic compound

Compounds that contain carbon

physcial change

The change in size, shape, or state of matter. Tearing a piece of paper in half or freezing water is an example of this.

chemical change

chemical reaction, Change in the arrangement of atoms or ions within molecules of the substance involved

Represented by a chemical equation

low quality matter

not concentrated matter often located deep underground or dispersed in the ocean or atmosphere and usually has little potential for use as a resource.

high quality matter

highly concentrated, typically found near the earth's surface, and has great potential for use as a resource

law of conservation of matter

Matter is not created nor destroyed in any chemical or physical change

monomer

A simple compound whose molecules can join together to form polymers

polymer

large compound formed from combinations of many monomers

CHONPS

The 6 elements most important in living things (Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorous, Sulfur)

Macromolecules

A very large organic molecule composed of many smaller molecules

energy

Energy stored in the bonds of chemical compounds

kinetic energy

energy of motion

potential energy

stored energy

thermal energy

the energy contained within a system that is responsible for its temperature

electromagnetic radiation

Radiation that has both electric and magnetic fields and travels in waves

first law of thermodynamics

Energy can be transferred and transformed, but it cannot be created or destroyed.

second law of thermodynamics

when energy is changed from one form to another, some useful energy is always degraded into lower quality energy (usually heat)

system

A group of parts that work together as a whole

feedback loops (positive and negative)

a process in which the outputs of a system are circled back and used as inputs, negative loop is when a product of a reaction leads to a decrease in that reaction

ecological tipping point

when an environmental problem reaches a threshold level, which causes a shift in the behavior of a natural system.

acid rain

rain containing high amounts of chemical pollutants

ocean acidification

decreasing pH of ocean waters due to absorption of excess atmospheric CO2 from the burning of fossil fuels