Chenistry science Vocab (Unit 1) Flashcards
Properties
charactersistic that describes a particular substance.
Freezing
change of state from liquid to solid
Ductility
solid that can be stretched into a long wire.
Element
Pure substance that cannot be broken
down into other substances; substance made up of
only one type of atom
Suspension
Cloudy mixture in which tiny particles of one substance are held within another, and the particles can be separated out.
Atomic mass
Mass of one atom of one element calculated from the total number of protons, neutrons, and electrons of that atom.
Non-Metals
Dull, brittle element that does not
conduct electricity
Chemical formula
Combination of symbols that
represent a compound; the formula identifies the
elements in the compound and the amount of each element. Example H2o
Chemical reaction
a reaction that takes place when
two or more substances react to form new substances example wood burning.
Conservation of mass
principle that matter is not
created or destroyed in a chemical reaction; the mass of the products always equals the mass of the reactants
WHMIS
Workplace Hazardous Materials
Information System; a system of easy-to-see warning symbols on hazardous materials
Sublimation
Change of state from solid to gas or gas to solid.
Conductivity
Ability of a substance to conduct electricity or heat
Compound
Chemical combination of two or more elements in a specific ratio
Colloid
cloudy mixture in which tiny particles of one substance are held within another and particles cannot be separated out from the other substance.
Period
Horizontal row in periodic table. Think of a sentence.
Metalloids
Element that has both metallic and non metallic properties.
Ionic compound
Pure substance formed when at
least one metal and one non-metal combine
Exothermic reaction
Chemical that releases energy
Closed system
An experiment where matter is not allowed in or out of the system.
States of matter
The states matter can take.
Ex Solid, Liquid
Deposition
Change of state from gas to solid.
Solubility
Degree to where a substance dissolves in solvent to make a solution.
Mixture
Combination of pure substances.
Protons
Positively charged atom in the nucleus of an atom.
Group
Vertical row on periodic table.
Alkali Metals
Group 1 elements in the periodic table ( not including hydrogen) They’re the most reactive metals.
Ions
Atom that has become electrically charged because of lost or increase in electron.
Endothermic reaction
Chemical reaction that absorbs energy.
Open system
Where matter can enter and escape.
Melting
The change if state from solid to liquid
Physical properties
Property that describes physical appearance and composition of a substance.
Chemical property
Description of how a substance
interacts with other substances.
Mechanical mixture
Mixture where components can be extracted once mixed. Reaction is reversible. Components are visible.
Electrons
Negatively charged particle the orbits the nucleus of an atom.
Atomic number
Number of protons in the nucleus of one atom of an element.
Alkali Earth Metals
Group 2 In periodic table. Reactivity is not as strong as the Alkali metals.
Polyatomic ions
Group of atoms acting as one.
Combustion
Chemical reaction that occurs when oxygen reacts with a substance to form a new
substance and give off energy
Catalyst
Substance that helps a chemical reaction to proceed more quickly
Evaporation
Change of state from liquid to gas.
physical change
A change that is physical ex ripping a paper
Chemical change
A change where the compositions of the substance are changed. ex burning something
Solution
homogeneous mixture; mixture of two or-more pure substances that looks like one substance
Neutrons
Neutral particle in the nucleus of an atom
Mass number
The sum of the number of protons and neutrons in an atom
Halogens
Group 17 on the periodic table. Most reactive non metals.
Molecule
Group of atoms joined by covalent bonds. (A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms.)
Corrosion
Slow chemical change that occurs when oxygen in the air reacts with a metal. ex rust
Enzyme
Catalyst involved in chemical reactions in living things
Condensation
Change of state from gas to liquid.
Malleability
Description of a substance that can be pounded or rolled into sheets.
Pure substance
Substance made of only one kind of matter, which has a unique set of properties
Aqueous solution
Solution in which water is the solvent
Periodic table
Table in which the elements are
organized by their physical and chemical properties
Metals
Shiny, malleable, ductile element that conducts electricity
Noble gases
Group 18. Most stable and unreactive metals.
Molecular compounds
Pure substance formed when non metals combine.
