Chapter 2 Flashcards
Mass
A measure of the quantity of matter in an object. On Earth, equivalent to the weight of an object.
Matter
Anything that takes up aspace and has mass.
Mass
A measure of the quantity of matter in any given object.
Constituents of an atom
protons, neutrons, electrons.
Electron
Negative charge
Proton
Positive charge.
Neutron
Neutral charge.
Nucleus
The core of an atom where protons and neutrons are.
Element
A substance that is “pure” in that it cannot be reduced to any simpler set of component substances through chemical processes.
Atomic number
The number of protons in the nucleus of an atom.
How are elements ordered on the periodic table?
According to atomic number.
Major elements found in the human body.
Oxygen, carbon, hydrogen.
Major elements found in the Earth’s crust.
Oxygen, silicon, aluminum, calcium, and iron.
Isotopes
A form of an element as defined by the number of neutrons contained in its nucleus. Different isotopes of an element have the same number of protons but differing numbers of neutrons.
An ___ is any form of matter that cannot be reduced to a simpler set of component substances through chemical means. Such forms of matter are defined by the number of ___ in their nuclei.
Element, proton.
Most forms of matter can come in several varieties, called isotopes, in accordance with the numbers of ___ in their nuclei.
Neutrons
Chemical bonding
The process of chemical combination and rearrangement.
Ionic bonding
A linkage in which two or more ions are bonded to each other by virtue of their opposite charge, so outer shells of each are completed.
Covalent bonding
A type of bonding where one atom can share one or more electrons with another atom. They can be polar and nonpolar.
When is an atom most stable?
When their outer shells are filled.
How many electrons are required to fulfill each energy level?
Two electrons for the first level and eight for subsequent levels.
Law of conservation of mass
States that matter is neither created nor destroyed in a chemical reaction.
Molecule
an entity consisting of a defined number of atoms covalently bonded together.
Electronegativity
The measure of the strength of attraction of an atom has for electrons that are being shared in a covalent bond. An atom with higher electronegativity will tend to pull electrons toward itself, away from atoms with lower electronegativity.
Polarity
A difference in electrical charge at one end as opposed to the other.
Polar covalent bond
A type of covalent bond in which electrons are shared unequally between atoms, so that one end of the molecule has a slight negative charge and the other end a slight positive charge. They are shaped unevenly due to the unequal distribution.
Nonpolar covalent bond
A type of covalent bond in which electrons are shared equally between atoms.