Terms

Unit 1A Vocabulary List

Filtration- process where solid particles are separated from a liquid by passing the mixture through a funnel (holds back the solid particles and allows the liquid to pass through)

Filtrate- liquid collected after it has been filtered

Percent recovery- percent of the original foul water sample that recovered as purified water

Purified water- water in its most natural, or clean state

Histogram- graph showing the data that different groups collected in a lab experiment

Range- the difference between the largest and smallest numbers in a data set

Average- sum of all values divided by the sum of the total number of values (also referred to as the mean)

Median- middle value of a data set

Electrical conductivity- test that focuses on the presence of dissolved, electrically charged particles in the water

Hydrochloric (water) cycle- the cycle that water goes through as it first evaporates from a body of water and turns into a gas, then falls as some form of precipitation (rain or snow), and after becomes either a form of ground water or surface runoff back into the body of water 

Direct water use- water use that can be directly measured

Indirect water use- hidden uses of water that may never have been considered

Gaseous state- form of water (water vapor)

Liquid state- form of water (liquid in lakes, rivers, oceans, clouds, rain)

Solid state- form of water (ice)

Surface water- water supply that originated in a river or other body of water

Groundwater- water supply that originated in a well

Aquifer- a water-bearing layer of rock, sand, or gravel

Unit 1B (B1-B4) Vocabulary List

Matter- anything that occupies space and has mass

Physical properties- properties that can be observed and measured without changing the chemical makeup of the substance

Density- mass of a material within a given volume (m/v)

Freezing point- temperature at which water transforms from a liquid into a solid

Aqueous solution- a water-based solution

Mixture- result when 2 or more substances combine, and yet they keep their individual properties

Heterogeneous mixture- mixture that is not the same, or uniform, throughout

Suspension- (heterogeneous) if the solid particles are large enough to settle out or can be separated by using filtration

Tyndall effect- the scattering of light once it is shone through a sample of purified water

Colloid- heterogeneous mixture where small, solid particles are still in the water

Homogeneous mixture- mixture that is the same, or uniform, throughout

Solution- always homogeneous mixtures

Solute- dissolved substance

Solvent- the dissolving agent

Particulate level- the level of the atoms and molecules

Atoms- building blocks of matter

Element- matter that is made up of only one kind of atom

Compound- substance that is composed of the atoms of two or more elements linked together chemically in certain fixed proportions

Chemical formulas- formulas that represent compounds and elements

Substance- an element and compound with a uniform and definite composition, as well as distinct properties

Molecule- smallest unit of a molecular compound that retains the properties of that substance

Unit 2 B.1 Vocabulary

Atmosphere- provides nitrogen, oxygen, argon, neon

Hydrosphere- layer of water (oceans, clouds, ice caps, glaciers, lakes, rivers, underground water supplies) and some dissolved minerals

Lithosphere- solid part of Earth, provides the greatest variety of chemical resources like petroleum and metal-bearing ores

• Contains the crust (band of soil and rock that obtain the raw materials needed to build homes and more), mantle, and core

 

Ore- naturally occurring rock or mineral that can be mined and from which it is possible to extract metal or other minerals

Minerals- naturally occurring solid compounds containing the element or group of elements of interest

Unit 2 A.6-A.11 Vocabulary

Atomic number- the number of proton in an atom; distinguishes atoms of different elements 

• 12 protons: magnesium 
• 6 protons: carbon 

Nucleus- positively charged central region of an atom that contains protons and neutrons

Mass number- the sum of the number of protons and neutrons in the nucleolus of an atom of a particular isotope (protons + neutrons= mass number)

Isotopes- atoms with the same number of protons but different number of neutrons

Periods- horizontal row in the periodic table; elements are listed in order of increasing atomic numbers and grouped according to similar properties

Periodic relationship- regular patterns among chemical and physical properties of elements arrayed in the periodic table

Group/ Family- vertical row in the periodic table (column); contains elements with similar properties

Alkali metal family- first column on the left side; highly reactive metal that forms an ECl chloride and E2O oxide

• A group of elements consisting of lithium, sodium, potassium, rubidium, cesium, and francium

Noble gas family- right most group of the periodic table; consists of very unreactive (chemically inert) elements

Halogen family- form 1- ions; group containing fluorine, chlorine, and bromine in a column to the left of the noble gases

Unit 2 A.5 Vocabulary

Combustion- chemical reaction with oxygen gas that produces thermal energy and light; burning

Conductor- a material that allows electricity (thermal energy) to flow through it

• Conducts electricity a light bulb is on

Nonconductor- a material that does not allow electrical current (or thermal energy) to flow through it

• Doesn’t conduct electricity light bulb off

Malleable- flattens without shattering when struck

Brittle- shatters into pieces

Unit 2 A.1-A.4 Vocabulary

Physical properties- a property that can be observed or measured without changing the identity of the sample of matter

• Color, density, odder

Physical change- a material stays the same, but its form appears to have changed

o   Melting, boiling, bending

Chemical properties- properties only observed or measured by changing the chemical identity of a sample of matter

Chemical change- when a substance changes to one or more new substances

• Burning wood, formation of a gas/solid

Luster- shinny and reflect light

Ductile- can be drawn into wires

Metals- a material possessing such as luster, ductility, conductivity, and malleability

• Iron (Fe), tin (Sn), copper (Cu), zinc (Zn)

Nonmetals- a material possessing properties such as brightness, lack of luster, and nonconductivity; nonmetals are often insulators

• Carbon (C) and oxygen (O)

Metalloids- a material with properties intermediate between those of metal and nonmetals

• Silicon (Si) and germanium (Ge)

Unit 1 C.8- C.13 Vocabulary

Heavy-metal ions- their atoms have greater masses than those of essential metallic elements, and can be harmful to humans or other organisms

• Lead
• Mercury

 

Green Chemistry- design that prevents pollution by eliminating the production and use of hazardous substances, related to heavy metal pollution

• To prevent heavy metals from getting into water à producing and using alternate materials that do not contain theses ions

pH scale- a way to measure and report the acidic, basic, or chemically neutral character of a solution

• Solution with pH values lower than 7 = Acidic
• Solutions with pH value greater than 7 = Basic

Alkaline- another name for a basic solution. Contains an excess of hydroxide ions (OH-)

Acids- ions or compounds that produce hydrogen ions (H+) or hydronium ions (H3O+) when dissolved in water

• Hydrochloric acid (HCl)

Bases- ions or compounds that produce hydroxide ions (OH-) ions when dissolved in water

• Sodium hydroxide (NaOH)

Chemically neutral- a substance that displays neither acidic nor basic characteristics

Molecular substances- a substance composed of molecules

• H2O
• CH4

Electronegativity- the ability of an elements atom to attract shared electrons when bonding within a compound (difference in electron attraction)

“like dissolves like”- the pattern or solubility behavior- polar substances dissolve in polar solvents and nonpolar substances dissolve in nonpolar solvents

Insoluble- refers to substances that are very, very slightly soluble in water

Gas-bubble trauma- when the total amount of dissolved gases (oxygen and nitrogen) reaches a state of supersaturation

• Causes gas bubbles to form in the blood and tissue of fish

 

C.4 + C.6 Vocabulary

Particulate level- atomic and molecular phenomena that cannot be easily observed

Polar molecule- a molecule with regions of partial positive and negative charge resulting from the uneven distribution of electrical charge

Concentration- refers to how much solute is dissolved in a specific quantity of a solvent or solution

Percent- another way to express concentration

Parts per million (ppm)- an expression of concentration; the number of units of solute found in one billion units of solution

Parts per billion (ppb)- an expression of concentration; the number of units of solute found in one billion units of a solution 

Unit 1 C.1- C.2 Vocabulary

Saturated- is when a solvent has dissolved as much solute as it can retain at a specific temperature, and therefore the solute settles at the bottom of the container because it cant dissolve anymore; even stirring the mixture will not make the crystals dissolve

Solubility- the maximum quality of a substance that will dissolve in a certain quality of water (solvent) to form a saturated solution at a specific temperature

Solubility curve- a graph indicating the solubility of a particular solute at different temperatures

Saturated solution- a solution in which the solvent contains as much dissolved solute as it normally can at that temperature (maxed out amount)

Unsaturated solution- a solution that contains less dissolved solute than the amount that the solvent can normally hold at that temperature

Supersaturated solution- an unstable solution; that contains more solute than can normally be dissolved at that temperature

o   Heat up a solvent, then cool it down and slightly tap the beaker or add a drop of a chemical à solid forms

Precipitate- when the extra solute appears as solid crystals and settles to the bottom of the beaker

  

Unit 1 B.8- B.11 Vocabulary

Protons- positively charged particles

Electrons- negatively charged particles

Electron cloud- a group of electrons (negative charge) revolving around the nucleus of an atom

Neutrons- electrically neutral particles

Ions- electrically charged atoms or groups of atoms

Ionic compounds- substances that are composed of positive and negative ions

• Always neutral because positive and negative electrical charges offset each other

Crystal- NaCl consists of positive and negative ions arranged in a three- dimensional network

• In solids, ionic compounds (table salt) ions are held together in crystals by attractions among negative and positive charges

Anion- negatively charged ion

Cation- positively charged ion

Polyatomic ion- an ion consisting of a group of bonded atoms

Confirming tests- tests that confirms that ions are present

Precipitate- insoluble solid substance that has separated from a solution

Qualitative tests- tests that identify the presence or absence of a particular substance in a sample

Quantitative tests- determines the amount of a specific substance present in a sample

Reference solution- a solution of known composition used as a comparison

Unit 1B.5- B.6 Vocabulary list

Macroscopic- a world filed with large scale (macro) readily observed things

Models- representations of atoms and molecules

Chemical symbols- an abbreviation of an element’s name.

• Such as N for nitrogen
• Fe for iron

Periodic table of elements- where elements are organized

Chemical formula- a symbolic expression representing the elements contained in a substance, together with subscripts that indicate the relative numbers of atoms of each element

Subscript- the number printed below the normal line of letters; indicates how many atoms of the element there are

For example: H2O, the subscript 2 indicates the total of H atoms

Chemical equations- chemical sentence; a symbolic expression summarizing a chemical reaction

2H2(g) + O2(g) --> 2H2O(g)

Chemical reactions- the process of forming new substances from reactants that involves the breaking and forming of chemical bonds

Reactants- starting materials in a chemical reaction

Products- substances formed in a chemical reaction

Diatomic Molecules- a molecule made up of two atoms (two bonded atoms of the same element) 

• chlorine gas- Cl2
• hydrogen gas- H2
• oxygen gas- O2