Praxis elementary education science
exam 5005 (Physical Science)
What are some characteristics of "matter" - answer--Matter is everything around you
--Atoms and molecules are all composed of matter
--Matter is defined as anything that has mass and takes up space
What are some characteristics of "elements" - answer--Elements are the alphabet in the
language of molecules.
--There are almost 120 known elements in the periodic table.
--Each element is a little bit different from the rest.
--When you combine elements, you can make millions of different molecules.
What is the structure of an atom? - answer--Consist of electrons surrounding a nucleus
that contains protons and neutrons
--•number of protons in an atom does not change, but the electron can change
Neutrons have what type of charge? - answerNeutral
Protons have what type of charge? - answerpositive one
Electrons have what type of charge? - answernegative one
What are some of the characteristics of an electron? - answer--Electrons are the
smallest of the three particles that make up atoms.
--Electrons are found in shells or orbitals that surround the nucleus of an atom.
--electrons are always moving. They spin very quickly around the nucleus of an atom.
--If you are an electron in the first shell, you are always closer to the nucleus than the
electrons in the second shell.
--Each shell can contain only a fixed number of electrons
What is the process for properly placing the electrons on the atoms? - answer--The first
shell can hold up to two electrons
-- the second shell can hold up to eight (2 + 6) electrons
--third shell can hold up to 18 (2 + 6 + 10) and so on. --The general formula is that the
nth shell can in principle hold up to 2(n2) electrons.
Define ions - answer--fewer or extra electrons can create a special atom either Cations
or Anions
Define Cations - answerhave fewer electrons in the atom; therefore the atom is has a
positive charge
, Define anions - answerhave extra electrons that create a negative charge atom
What are some characteristics of isotopes - answer--when the number of neutrons
change
--Chemical properties stay the same due same number of protons as electrons
--Isotopes contain a different mass
Why is the atomic mass and number important? - answer--That number tells you the
number of protons in every atom of the element. The atomic number is also called the
proton number.
--Protons in an atom give the Atomic number
What are the characteristics of Radioactive Decay? - answer-- also known as nuclear
decay or radioactivity
--is the process by which the nucleus of an unstable atom loses energy by emitting
radiation
including alpha particles, beta particles, gamma rays and conversion electrons
--A material that spontaneously emits such radiation is considered radioactive.
What are the characteristics of the periodic table of elements? - answer--The periodic
table is organized like a big grid. Each element is placed in a specific location because
of its atomic structure. As with any grid, the periodic table has rows (left to right) and
columns (up and down). Each row and column has specific characteristics.
--When you look at the periodic table, each row is called a period
--All of the elements in a period have the same number of atomic orbitals.
--For example, every element in the top row (the first period) has one orbital for its
electrons. All of the elements in the second row (the second period) have two orbitals
for their electrons. As you move down the table, every row adds an orbital. At this time,
there is a maximum of seven electron orbitals.
What are compound elements? - answer2 or more elements combined
Characteristics of chemical changes - answer--occurs when the bonds between atoms
in a molecule are created or destroyed.
--If the formula of water were to change, that would be a chemical change. If you could
add a second oxygen atom to a water molecule, you would have hydrogen peroxide
(H2O2). The molecules would not be water anymore.
Characteristics of physical changes - answer--these changes relate to changes in the
immediate environment such as temperature, pressure, and other physical forces.
--Generally, the basic chemical structure does not change when there is a physical
change.
--Molecules can move from one physical state to another (phase change) and not
change their basic structure. Oxygen (O2) as a gas has the same chemical properties
exam 5005 (Physical Science)
What are some characteristics of "matter" - answer--Matter is everything around you
--Atoms and molecules are all composed of matter
--Matter is defined as anything that has mass and takes up space
What are some characteristics of "elements" - answer--Elements are the alphabet in the
language of molecules.
--There are almost 120 known elements in the periodic table.
--Each element is a little bit different from the rest.
--When you combine elements, you can make millions of different molecules.
What is the structure of an atom? - answer--Consist of electrons surrounding a nucleus
that contains protons and neutrons
--•number of protons in an atom does not change, but the electron can change
Neutrons have what type of charge? - answerNeutral
Protons have what type of charge? - answerpositive one
Electrons have what type of charge? - answernegative one
What are some of the characteristics of an electron? - answer--Electrons are the
smallest of the three particles that make up atoms.
--Electrons are found in shells or orbitals that surround the nucleus of an atom.
--electrons are always moving. They spin very quickly around the nucleus of an atom.
--If you are an electron in the first shell, you are always closer to the nucleus than the
electrons in the second shell.
--Each shell can contain only a fixed number of electrons
What is the process for properly placing the electrons on the atoms? - answer--The first
shell can hold up to two electrons
-- the second shell can hold up to eight (2 + 6) electrons
--third shell can hold up to 18 (2 + 6 + 10) and so on. --The general formula is that the
nth shell can in principle hold up to 2(n2) electrons.
Define ions - answer--fewer or extra electrons can create a special atom either Cations
or Anions
Define Cations - answerhave fewer electrons in the atom; therefore the atom is has a
positive charge
, Define anions - answerhave extra electrons that create a negative charge atom
What are some characteristics of isotopes - answer--when the number of neutrons
change
--Chemical properties stay the same due same number of protons as electrons
--Isotopes contain a different mass
Why is the atomic mass and number important? - answer--That number tells you the
number of protons in every atom of the element. The atomic number is also called the
proton number.
--Protons in an atom give the Atomic number
What are the characteristics of Radioactive Decay? - answer-- also known as nuclear
decay or radioactivity
--is the process by which the nucleus of an unstable atom loses energy by emitting
radiation
including alpha particles, beta particles, gamma rays and conversion electrons
--A material that spontaneously emits such radiation is considered radioactive.
What are the characteristics of the periodic table of elements? - answer--The periodic
table is organized like a big grid. Each element is placed in a specific location because
of its atomic structure. As with any grid, the periodic table has rows (left to right) and
columns (up and down). Each row and column has specific characteristics.
--When you look at the periodic table, each row is called a period
--All of the elements in a period have the same number of atomic orbitals.
--For example, every element in the top row (the first period) has one orbital for its
electrons. All of the elements in the second row (the second period) have two orbitals
for their electrons. As you move down the table, every row adds an orbital. At this time,
there is a maximum of seven electron orbitals.
What are compound elements? - answer2 or more elements combined
Characteristics of chemical changes - answer--occurs when the bonds between atoms
in a molecule are created or destroyed.
--If the formula of water were to change, that would be a chemical change. If you could
add a second oxygen atom to a water molecule, you would have hydrogen peroxide
(H2O2). The molecules would not be water anymore.
Characteristics of physical changes - answer--these changes relate to changes in the
immediate environment such as temperature, pressure, and other physical forces.
--Generally, the basic chemical structure does not change when there is a physical
change.
--Molecules can move from one physical state to another (phase change) and not
change their basic structure. Oxygen (O2) as a gas has the same chemical properties
