H Chem: Unit 2

anything that takes up space and displays the properties of mass and inertia

a resistance to change

distinguishable qualities or attributes of a sample of matter

a state of matter in which the bonds can be rearranged, broken, and reformed repeatedly, the volume is fixed but the substance takes the shape of its container

a state of matter in which there is a fixed volume and shape, the atoms don't move much and are packed tightly together

a state of matter in which the bonds of the atoms are broken and nonexistent, there is no fixed volume or shape, conforms to whatever volume available

salt water

does not have a definite composition, where things are mixed but not chemically bonded or changed, can be separated by physical means

things such as elements and compounds that are chemically bonded and have a definite composition, has a fixed chemical formula that can only be separated by chemical means

a homogenous mixture

in a solution, the stuff that gets dissolved (usually has the lowest volume in the mixture)

in a solution, the substance that does the dissolving (usually has the highest volume in the mixture)

the smallest unit of matter

• protons p⁺
• neutrons n^o
• electrons e^-

a type of atom that has a specific number of subatomic particles; cannot be broken down into other substances by chemical methods

number that tells how many protons an atom has

two or more atoms covalently bonded together, does not include ions (ionic bonds)

the exchange or sharing of electrons

a characteristic not related to change; things like odor, color, volume, state, density, melting point and boiling point

the ability of a substance to change

decomposition of water by an electric current, a chemical process

a change that does not produce a new substance, involves a change in one or more physical properties

a change that produces a new substance with new properties

the occurrence of a chemical change

a substance composed of a given combination of elements that can be broken down into those elements by chemical methods, has at least two different types of atoms

mixture that is the same throughout

mixture where the regions may have different properties

separating the ingredients of a mixture by boiling water and causing the solid components to e left behind

using a mesh to have the liquid separate from the solid ad leave behind the solid remnants

intensive and extensive

do not depend of amount of matter present

depend on the amount of matter that is present (e.g. volume, mass, size, shape)

to form an insoluble compound either by reacting two salts or by changing the temperature to affect solubility; name of solid formed by precipitation reaction

the state of matter that a substance is in

a substance made by melting two or more elements together, at least one of them a metal

the gaseous phase of water

means that any sample of the substance will have the same properties and appearance

a positive ion; an atom where there are more protons than electrons

a negative ion; an atom where there are more electrons than protons

a sum of the protons and neutrons in an atom

the average of the masses of the known isotopes of an atom

an atom with the same number of protons but different number of neutrons; has a different mass because it has a different number of neutrons

carbon 12 (more abundant), carbon 14

putting atoms together

the vertical columns of the periodic table (there are 18), where elements have similar properties

atomic number

metals, metalloids, non-metals

z

electrons

filtration, distillation, gas-liquid chromatography

heat, electrolysis

when elements are arranged by increasing z (atomic number), properties repeat periodically

the rows in the periodic table, there are seven

alkali metals (excludes H)

alkaline earth metals

noble gases

halogens

star-step line in the periodic table that separates metals from non-metals

subatomic particles located in the atom's nucleus with a positive charge, have mass

subatomic particles located in an atom's nucleus, have no charge, have mass

subatomic particles located in the electron cloud which surrounds the nucleus, have negative charge, have virtually no mass

aka free atom; an atom where the number of protons and electrons are the same, overall charge is zero

the substances present before a reaction

the substances present after a reaction

a given compound has the same composition (ratio of elements), regardless of where it comes from

• elements are composed of atoms
• atoms in an element are the same
• different atoms can combine to form compounds (compounds have a definite composition)
• atoms cannot be chemically destroyed, but they can be chemically rearranged

something that expresses the types and numbers of atoms in each unit (molecule) of a given compound

the abbreviation of the element's name, like Na

elements in group 1A-8A, all elements excluding the transition metals

Mendeleev

particles within the nucleus breaking down and/or being released

gamma rays

mass and energy

less mass = more energy and vice versa

the amount of time required for one half of the original mass to decay

• fraction remaining = (1/2)ⁿ
• mass remaining=(original mass)(fraction remaining)
• n= total time elapsed/ half life time

116; 88

the first scientist generally accredited with putting the study of chemistry on a firm experimental basis

neutrons are slightly heavier

no, the neutrons can vary

an element that has some properties common to both metallic and nonmetallic elements

4/2 He

0/-1 e

0/+1 e

compound

atomic mass number

radioactive

element

compound

element

atom

nucleus

symbol

contain atoms of different elements and be chemically combined in a definite proportion

true