NS&E L4 202(4-5) Finals Vocabulary (Combined w/o MYE Vocabulary)

Proton

Positively charged part of an atom, gives the atom it's identity

Electron

Negatively charged part of an atom, is responsible for bonding

Neutron

Neutral part of an atom, holds the nucleus together since the protons would naturally want to repel each other

Nucleus

Center of an atom, that contains protons and neutrons

Energy Level

Path around the nucleus, where the electrons reside

Proton's charge

Positive

Electron's charge

Negative

Parts of the nucleus

Protons and neutrons

Neutron's charge

Neutral

Atomic number

Number of protons in the nucleus of the atom, in an neutral atom it is also the number of electrons

Isotope

An atom with a varying number of neutrons

Atoms of the same element that have different numbers of neutrons

Ion

An atom or group of atoms that has a positive or negative charge. Because of the number of electrons and protons are not the same.

covalent bonding - definition

A type of atomic bonding where bonds formed when atoms share one or more pairs of electrons

ionic bonding - definition

A type of atomic bonding where the bonds that forms as a result of the attraction between positively and negatively charged ions

metallic bonding - definition

A type of atomic bonding where positively charged metallic ions, are surrounded by a sea of electrons

covalent bonding - image example

ionic bonding - image example

metallic bonding - image example

anion - definition

A negatively charged ion

cation - definition

A positively charged ion

anion - image example

cation - image example

atom

Basic unit of matter that retains all the properties of the element

Atomic Bonding

Atomic bonding is chemical bonding. Chemical bonding is the physical process that is responsible for the interactions between atoms and molecules. Different types include: covalent, ionic, metallic, etc.

Relative Atomic Mass

The mass of an atom relative to that of carbon-12. This is approximately the sum of the number of protons and neutrons in the nucleus. Where more than one isotope exists, the value given is the abundance weighted average.

Coefficient

A number placed in front of a chemical formula to indicate how many particles there are. Ex: 2FeO means two particles of FeO and FeO. Used to balance equations to demonstrate the law of conservation of matter

Subscript

The little number to the lower right of a symbol that indicates how many atoms of that symbol are included in that particle. Ex. H₂O the 2 means that there are two hydrogen atoms and one oxygen atom bonded together to form a single water molecule. Indicates BONDING

Molecule

A group of nonmetal atoms bonded together by covalent bonds to form a covalent particle. It is the smallest piece of a covalent substance that retains all the properties of that substance. (H₂ and CO₂ for example)

Formula Unit

A group of ions bonded together by ionic bonds to form an ionic compound. This is the smallest piece of an ionic compound that retains all the properties of that compound. They are composed of metal and nonmetal atoms.

Synthesis Reaction

A chemical reaction where two or more reactants combine chemically to form one new product.

Ex. 2Cu + O₂ → 2CuO

Copper + Oxygen → Copper Oxide

Double Replacement Reaction

A chemical reaction where two compound reactants break apart to recombine chemically and form two new compound products. Each reactant is formed from a metal bonded (ionically) with a nonmetal. To form the products the metals switch places. (*Note, in this special case, Hydrogen (H) is acting like a metallic element but still makes a covalent bond with chlorine!)

CuO(s) + 2HCl(aq) → CuCl₂(aq) + H₂O(l)

Copper Oxide + Hydrochloric Acid → Copper Chloride + Water

Combustion Reaction

A rapid reaction between oxygen and a hydrocarbon fuel that produces carbon dioxide, water, and thermal energy.

An example of the base of an unbalanced combustion reaction is:

CxHy + O₂ → CO₂ + H₂O

Ion

A particle with a positive or negative charge. It forms when an atom has an unequal number of protons and electrons. It may have a (cation) positive charge (loss of electrons to have more protons than electrons) or an (anion) negative charge (gain of electrons to have more electrons than protons).

Valence Electrons

The electrons available to be lost, gained, or shared during bonding. Located in the outermost energy level of the atom.

Covalent bond

The bond between atoms that form when valence electrons are shared. A characteristic of nonmetals bonding with nonmetals (ex H₂O and O₂)

Ionic bond

Bond between atoms that forms from the transfer of electrons when valence electrons are lost from one atom and gained by another atom creating ions that are attracted to each other. A characteristic of metals bonding with nonmetals (ex NaCl).

Diatomic

Means being made from two atoms that are the same type bonded together by covalent bonds: H₂, O₂, N₂, Cl₂, F₂, Br₂ ,I₂.

Lewis Dot Structure

diagram of a molecule using dots to represent valence electrons an atom has

polar molecule

A molecule in which one side of the molecule is slightly negative and the opposite side is slightly positive, water is an example of a polar molecule

nonpolar molecule

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

Compound

A substance comprises atoms of two or more different elements joined by chemical bonds.

metallic bond

an attraction between a positive metal ion and the electrons surrounding it, electrons are a "sea" around the positive metal ions

Hydrogen bond

A type of weak molecular chemical bond is formed when the slightly positive hydrogen atom of one polar covalent molecule is attracted to the slightly negative atom of a polar covalent bond in another molecule.

Anion

A negatively charged particle, where there are more electrons than protons present in the particle

Cation

A particle with a positive charge, where there are more protons than electrons present in the particle

Single replacement reaction

A chemical reaction where one compound reactant breaks apart to recombine chemically and form one new product.

Br₂ + 2KF --> 2KBr + F₂

Decomposition Reaction

a reaction in which a single compound breaks down to form two or more simpler substances

2H₂O --> H₂ + O₂

Element

A pure substance made of only one kind of atom, for example Carbon, there are unique 118 elements on the Periodic Table

Periodic Table

A table that shows the elements, their atomic number, symbol, and average atomic mass; elements with similar chemical properties are grouped together.

force

A push or a pull

pressure (definition)

the amount of force exerted per unit area of a surface

viscosity

A liquid's resistance to flowing

newtonian fluid

constant viscosity, does not change with applied stress

nonnewtonian fluid

viscosity can change depending on the applied stress

density

mass/volume, kg/m³, g/cm³ = g/mL

velocity

the speed of an object in a particular direction

cylinder volume (equation)

V=πr²h, Volume = pi radius radius * height

weight (definition)

A measure of the force of gravity on an object

weight (equation)

weight = mass x gravity, w =mg

pressure (equation)

Pressure = Force/Area (P=F/A)

newton (definition)

SI unit of force, 1 N = (kilogram*meter)/second²

pascal (definition)

SI unit of pressure, 1 Pa = 1 Newton/1 meter²

total pressure

sum of all the pressures felt by an object, at the bottom of the pool you would feel the pressure of the water AND the pressure of earth's atmosphere

Liquid pressure (equation)

density gravity depth

flux meter

Measures the volume of a fluid going through a cross-sectional area per unit of time

mass flow rate

the amount of mass flowing through a cross-section per unit time (kg/s)

volume flow rate

the volume of a fluid flowing through a cross-section per unit time (m³/s)

battery

A device that is used to convert chemical energy into electric energy. A group of voltaic cells connected together in a series or parallel (positive to negative)connection.

Ion

An atom with either a positive charge (+) because it has more protons than electrons, or a negative charge (-) because it has more electrons than protons

Current

An electric current is a flow of electric charge. In electric circuits, this charge is often carried by moving electrons in a wire. The unit is Ampere, 1 coulomb of energy/1 second of time

Electrolyte

A chemical medium that allows the flow of electrical charge between the cathode and anode. When a device is connected to a battery — a light bulb or an electric circuit — chemical reactions occur on the electrodes that create a flow of electrical energy to the device.

Copper Penny

The copper side of the battery is the positive side of our battery (cathode)

Zinc Washer

The zinc side of the battery is the negative side of our battery (anode)

Cardboard

Used to hold the electrolyte between the penny and the washer

Cation

A positively charged ion (#protons > #electrons in the atom)

Anion

A negatively charged ion (#electrons > #protons in the atom)

Repulsive Force

Like particles repel like particles. The electrons in our battery feel a mutual repulsion from other free electrons

What creates the electricity in our battery

Persuading a couple of electrons to leave an atom (or join an atom) takes very little energy. For instance, when zinc reacts chemically with an acid, it can liberate electrons. (Nature of Electricity - Charles Platt)

Why do the electrons want to move in our battery?

As electrons accumulate on the zinc electrode. They feel a mutual force of repulsion because like charges repel each other. (Nature of Electricity - Charles Platt)

Where do the free electrons go in our battery

As soon as we open up a pathway from a zinc

electrode crowded with electrons to a copper electrode, which contains "holes" for the electrons, their mutual repulsion makes them try to escape from each other to their new home as quickly as possible. (Nature of Electricity - Charles Platt)

Why does the battery stop working after a while?

The process (of generating electric current) continues until the zinc-acid reaction grinds to a halt, usually because it creates a layer of a compound such as zinc oxide, which won't react with acid and prevents the

acid from reacting with the zinc underneath. This is why

your zinc electrode may have looked sooty when you pulled it out of the acidic electrolyte. (Nature of Electricity - Charles Platt)

cathode (galvanic cell)

considered positive electrode. Electrons move from negative (low potential) to positive (high potential). Anode considered negative electrode here.

anode (galvanic cell)

is considered the negative electrode "The aNode of a galvaNic cell is always Negative"

Conduction

Form of heat transfer where heat energy is directly transferred between particles through particle collisions or direct contact.

Convection

The transfer of heat by the movement of a fluid

Fluid

any substance that can flow and take the shape of the container that holds it

q

The variable used for Thermal Energy

Δ (Delta)

The greek letter used to indicate change

Latent Heat of Fusion (Lf)

The amount of thermal energy absorbed per gram as solid melts (fuses) at its melting point. The same amount of heat per gram must be released to freeze the substance.

Latent Heat of Vaporization (Lv)

The amount of thermal energy absorbed per gram as a liquid boils (vaporize) at its boiling point. The same amount of heat per gram must be released to condense the substance.

c

Heat capacity is the number of joules of energy needed to raise the temperature of a substance by one degree. In physics, it is Cp; in chemistry it is c

Density

Mass per unit volume of a substance

Radiation

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

Solid

A state of matter that has a definite shape and a definite volume

Liquid

A state of matter that has no definite shape but has a definite volume.

Gas

A state of matter with no definite shape or volume

Boiling Point

The temperature at which a liquid changes to a gas

Melting Point

the temperature at which a substance changes from a solid to a liquid

Phase change

a change from one state (solid or liquid or gas) to another without a change in chemical composition

Melt

change from a solid to a liquid