General Chemistry placement Exam A+
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molecule - Answer- two nonmetal atoms combined form a covalent compound called a
diatomic molecules - Answer- H2,O2,F2
Matter - Answer- Anything that has mass and takes up space
Element - Answer- A substance that cannot be broken down into simpler substances
Compound - Answer- A pure substance made of two or more elements CHEMICALLY
combined.
Compound - Answer- Can be decomposed by chemically
Mixture - Answer- A PHYSICAL blend of two or more components
(aq) - Answer- aqueous mixture, a substance is dissolved in water
homogeneous mixture - Answer- A mixture that is so evenly mixed that you can't see all
of the different parts. Ex. Air, kool-aid
heterogeneous mixture - Answer- A mixture in which different materials can be seen
easily.
Ex. soil, chocolate chip cookies
filtration - Answer- process to separate a solid "precipitate" from a liquid
sublimation - Answer- phase change from (s) --> (g)
empirical formula - Answer- A formula showing the lowest whole number ratio of atoms
in a compound. Can't be reduced.
solid - Answer- A state of matter that has a definite shape and a definite volume
liquid - Answer- A form of matter that flows, has constant volume, and takes the shape
of its container
Bromine (Br) and Mercury (Hg) - Answer- only two liquids on the periodic table
gas - Answer- A state of matter with no definite shape or volume
gas - Answer- will uniformly and completely fill a container
, gases - Answer- physical property most all nonmetals and group 18
physical property - Answer- A characteristic of a substance that does not involve a
chemical change. Ex. melting/boiling point, solubility, density, color, or hardness.
properties - Answer- used to identify or recognize matter (objects).
chemical property - Answer- describes how matter reacts when it changes chemically
into another substances. Ex. reactivity with acid, base or with air to rust, flammability,
decomposition.
physical/phase change - Answer- (s)-->(l)-->(g), diluting, crush, cut. Still same
substance.
Density - Answer- A physical property. Specific to every element.
Chemical symbol - Answer- One capital letter, or a capital letter and a lower case letter
together. Mass on upper left side, and atomic # on lower left side.
Conservation of Mass - Answer- Equal # of atoms on both sides of a chemical equation
Democritus - Answer- Greek philosopher that said all matter is made of tiny particles
called "atomos" or atoms
JJ Thomson - Answer- used the cathode ray tube to discover electrons
Rutherford - Answer- Gold foil experiment: (atom is mostly empty space, atoms contains
a dense, positively charged nucleus); discovered protons.
Wave Mechanical Model - Answer- Modern model of the atom, atoms have electrons in
"orbitals" that are like clouds around the nucleus
Bohr Model - Answer- A model resembling planets revolving around the sun in orbits,
useful in visualizing the structure of atoms.
Proton - Answer- A subatomic particle that has a positive charge and that is found in the
nucleus of an atom. Mass = 1 amu
Atomic number - Answer- Equals the number of protons in the nucleus (never changes)
Electron - Answer- A tiny, negatively charged particle that moves around the nucleus of
an atom.
# of protons - Answer- Equals # of electrons in a neutral atom
Pass Already Passed New Update
molecule - Answer- two nonmetal atoms combined form a covalent compound called a
diatomic molecules - Answer- H2,O2,F2
Matter - Answer- Anything that has mass and takes up space
Element - Answer- A substance that cannot be broken down into simpler substances
Compound - Answer- A pure substance made of two or more elements CHEMICALLY
combined.
Compound - Answer- Can be decomposed by chemically
Mixture - Answer- A PHYSICAL blend of two or more components
(aq) - Answer- aqueous mixture, a substance is dissolved in water
homogeneous mixture - Answer- A mixture that is so evenly mixed that you can't see all
of the different parts. Ex. Air, kool-aid
heterogeneous mixture - Answer- A mixture in which different materials can be seen
easily.
Ex. soil, chocolate chip cookies
filtration - Answer- process to separate a solid "precipitate" from a liquid
sublimation - Answer- phase change from (s) --> (g)
empirical formula - Answer- A formula showing the lowest whole number ratio of atoms
in a compound. Can't be reduced.
solid - Answer- A state of matter that has a definite shape and a definite volume
liquid - Answer- A form of matter that flows, has constant volume, and takes the shape
of its container
Bromine (Br) and Mercury (Hg) - Answer- only two liquids on the periodic table
gas - Answer- A state of matter with no definite shape or volume
gas - Answer- will uniformly and completely fill a container
, gases - Answer- physical property most all nonmetals and group 18
physical property - Answer- A characteristic of a substance that does not involve a
chemical change. Ex. melting/boiling point, solubility, density, color, or hardness.
properties - Answer- used to identify or recognize matter (objects).
chemical property - Answer- describes how matter reacts when it changes chemically
into another substances. Ex. reactivity with acid, base or with air to rust, flammability,
decomposition.
physical/phase change - Answer- (s)-->(l)-->(g), diluting, crush, cut. Still same
substance.
Density - Answer- A physical property. Specific to every element.
Chemical symbol - Answer- One capital letter, or a capital letter and a lower case letter
together. Mass on upper left side, and atomic # on lower left side.
Conservation of Mass - Answer- Equal # of atoms on both sides of a chemical equation
Democritus - Answer- Greek philosopher that said all matter is made of tiny particles
called "atomos" or atoms
JJ Thomson - Answer- used the cathode ray tube to discover electrons
Rutherford - Answer- Gold foil experiment: (atom is mostly empty space, atoms contains
a dense, positively charged nucleus); discovered protons.
Wave Mechanical Model - Answer- Modern model of the atom, atoms have electrons in
"orbitals" that are like clouds around the nucleus
Bohr Model - Answer- A model resembling planets revolving around the sun in orbits,
useful in visualizing the structure of atoms.
Proton - Answer- A subatomic particle that has a positive charge and that is found in the
nucleus of an atom. Mass = 1 amu
Atomic number - Answer- Equals the number of protons in the nucleus (never changes)
Electron - Answer- A tiny, negatively charged particle that moves around the nucleus of
an atom.
# of protons - Answer- Equals # of electrons in a neutral atom
