Aleks Placement Test: Chemistry UPDATED Exam Questions and CORRECT Answers

Aleks Placement Test: Chemistry
UPDATED Exam Questions and
CORRECT Answers
Matter - Correct Answer- Anything that has mass and takes up space; made of atoms


Atoms - Correct Answer- Basic unit of matter which cannot be broken down and contain
mostly empty space; contains three parts: the electron, proton, and neutron


Elements - Correct Answer- A pure substance that contains only one type of atom


Compound - Correct Answer- Two or more elements that are chemically bonded; includes
ionic and covalent


Mixture - Correct Answer- Two or more substances that are together but not bonded


Pure Substance - Correct Answer- Substance that contains only one kind of compound


Bose-Einstein Condensate - Correct Answer- The state of matter with the lowest energy;
basically a very cold solid


Solid - Correct Answer- A state of matter with strong bonds


Liquid - Correct Answer- A state of matter with weak bonds


Gas - Correct Answer- A state of matter with no bonds


Plasma - Correct Answer- The state of matter with the highest energy; it uses ionization
instead of bonds


Robert Boyle - Correct Answer- First to define an element; any substance is a substance
unless it can be broken down

,John Dalton - Correct Answer- Used and combined previous ideas to discuss the atom;
elements are made of atoms; all atoms of an element are identical; atoms of different
elements are different; law of constant composition; atoms are invisible


Law of Constant Composition - Correct Answer- Atoms of one element can combine with
other elements to form compounds; a given compound always has the same relative numbers
and types of atoms


J.J. Thomson - Correct Answer- Discovered electrons and protons and developed the plum
pudding model of an atom


Electrons - Correct Answer- The negatively charged particle in an atom; circles around the
nucleus in the electron cloud


Proton - Correct Answer- The positively charged particle in an atom; located in the nucleus;
determine the element


Neutron - Correct Answer- The neutral particle in an atom; it has no charge and is located in
the nucleus


Plum Pudding Model - Correct Answer- A model of the atom that depicts a sphere of positive
charge with electrons scattered throughout


Ernest Rutherford - Correct Answer- Conducted an experiment in which he shot alpha
particles at gold foil; roved there was a small, dense nucleus with a positive charge and that
protons are positive


Metals - Correct Answer- Elements located on the left side of the periodic table that want to
lose electrons


Characteristics of Metals - Correct Answer- - Malleable
- Ductile
- Conductive
- Lustrous

, Malleable - Correct Answer- The ability to be molded into shapes


Ductile - Correct Answer- The ability to be pulled into wire


Conductive - Correct Answer- The ability to allow heat or electricity to pass through an
object


Lustrous - Correct Answer- The ability to be shiny


Nonmetals - Correct Answer- Elements located on the right side of the periodic table that
want to gain electrons


Metalloids - Correct Answer- Elements placed in a stair-step line between metals and
nonmetals; they have characteristics of both


Diatomic Molecules - Correct Answer- Elements that occur in pairs in their natural state;
hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, iodine


Electronegativity - Correct Answer- The ability of a molecule to attract electrons to it;
increases as you move left to right in the table and decreases as you move top to bottom;
fluorine is the hardest


Atomic Radius - Correct Answer- The radius of an atom; decreases as you move left to right
and increases as you move top to bottom


Ionization Energy - Correct Answer- The energy needed to rip off an electron; increases as
you move left to right and decreases as you move top to bottom


Ion - Correct Answer- An atom that has gained or lost electrons


Anion - Correct Answer- An atom that gains electrons and has a negative charge; nonmetals