Ch.15 Atoms Test
The atomic number of fluorine is 9 and its mass number is 19, so it has _______ neutrons
10 neutrons
Compared to the mass of a hydrogen atom, the mass of an oxygen atom is ________ times greater
16 times greater
Magnesium: Atomic #12 How many electrons are in it's third level?
2
Sodium has a total of 11 electrons. The number of electrons in the first energy level of sodium is
2
If lithium has a mass number of 7 and an atomic number of 3, a lithium atom contains __protons, __ neutrons, and ___electrons
3 protons, 4 neutrons, 3 electrons
A certain atom has 26 protons, 26 electrons, and 30 neutrons. Its mass number is _______
56
Aluminum: Atomic #13 How many electrons are in it's second level?
8
The average of all the masses of the isotopes of a particular element
Atomic mass
If a pair of helium nuclei are fused together, the results is ________
Beryllium
Carbon: Symbol Atomic number Number of protons Number of neutrons Mass number
C 6 6 6 12
If two protons are removed from an oxygen nucleus, the result is ______
Carbon
What is it that electrons have that protons always have in equal magnitude?
Charge
Chlorine-37: Symbol Atomic number Number of protons Number of neutrons Mass number
Cl 17 17 20 37
Chlorine-35: Symbol Atomic number Number of protons Number of neutrons Mass number
Cl 17 17 18 35
Copper: Symbol Atomic number Number of protons Number of neutrons Mass number
Cu 29 29 35 64
Atomic particles found in energy levels outside the nucleus
Electrons
Each energy level of an atom has a max number of _____ it can hold
Electrons
The chemical properties of matter comes mostly from its
Electrons
An electric force between the nucleus of an atom and its electrons causes the _________ to move in an orbit around the _________
Electrons to move in an orbit orbit around the nucleus
Some alpha particles fired through a gold foil bounce backward by _____
Electrostatic repulsion when close to gold nuclei
Iron: Symbol Atomic number Number of protons Number of neutrons Mass number
Fe 26 26 30 56
Helium: Symbol Atomic number Number of protons Number of neutrons Mass number
He 2 2 2 4
If one neutron is added to a helium nucleus, the result is _____
Helium
Atoms of the same element with different numbers of neutrons are called _______
Isotopes
Atoms whose nuclei contain the same number of protons but different numbers of neutrons
Isotopes
Which has the greatest number of protons in its nucleus? Gold Mercury Lead Silver
Lead
The sum of the protons and neutrons in the nucleus of a particular kind of atom
Mass number
The Bohr model of the atom is similar to a
Miniature solar system
Because atoms are too small to study directly ,scientists use ________ to study them
Miscroscopes
Nitrogen: Symbol Atomic number Number of protons Number of neutrons Mass number
N 7 7 7 14
Sodium: Symbol Atomic number Number of protons Number of neutrons Mass number
Na 11 11 12 23
To change mercury into gold, a pair of protons must be: removed from the mercury nucleus or added to the mercury nucleus?
Neither of these.
If two protons are added to an oxygen nucleus, the result is _________
Neon
Which of the following are electrically neutral? Proton Neutron Electron
Neutron
Atomic particles that are electrically neutral
Neutrons
Atoms heavier than hydrogen were made by
Nuclear fusion
Atoms heavier than hydrogen were made by __________
Nuclear fusion
Oxygen: Symbol Atomic number Number of protons Number of neutrons Mass number
O 8 8 8 16
In an electrically neutral atom, the number of protons in the nucleus is balanced by an equal number of _____
Orbital electrons
In an electrically neutral atom, the number of protons in the nucleus is balanced by an equal number of ________
Orbital electrons
Dot diagrams are used to represent _________
Outer electrons
Because the nucleus of an atom contains protons, it has a _______ charge
Positive
One atomic mass unit describes the mass of a ________ or _______
Proton Neutron
The nucleus of an atom is made up of _____ and ______
Protons and neutrons
The mass of an atom, in atomic mass units, is equal to the number of ________ and __________ in its __________
Protons and neutrons in its nucleus
The atomic number of an element tells how many _________ are in the ________
Protons are in the nucleus
Which is the smallest particle listed below? Molecule Atom Proton Neutron Quark
Quark
Which is the smallest particle listed below? Molecule Atom Proton Neutron Quark
Quark
Particles of matter that make up protons and neutrons are ______
Quarks
Brownian motion has to do with the ________
Random motions of atoms and molecules
Sulfur: Symbol Atomic number Number of protons Number of neutrons Mass number
S 16 16 16 32
Assuming all the atoms exhaled by Julius Caesar in his last dying breath are still in the atmosphere, then we probably breathe one of those atoms with each
Single breath
Electrons differ from protons and neutrons because electrons have a much ________ mass
Smaller
If we doubled the magnifying power of the most powerful optical microscope in the world, we would_______
Still not be able to see an atom
One or two letters used to represent an atom of a particular element
Symbol
What makes an element distinct?
The number of neutrons
J.J Thompson's discovery of negatively charged particles in atoms indicated that
There are particles smaller than atoms
T or F: There are only about 100 different kinds of atoms that combine to form all substances
True
How many different elements are in a water molecule?
Two
Which of these atoms has the greatest number of electrons: Helium Carbon Iron Gold Uranium
Uranium
Which of these atoms has the most mass? Hydrogen Uranium Lead Iron
Uranium
There are about and many atoms of air in our lungs at any moment as there are breaths of air in the atmosphere of the
Whole world
Nuclei of atoms that make up a newborn baby were made in the
ancient stars
A particle that moves around the nucleus is a(n)
electron
The volume of matter comes mostly from its
electrons
The reason a granite block is mostly empty space is because the atoms in the granite are
mostly empty space themselves
A chemical symbol represents the _____ of an element
name
Solid matter is mostly empty space. The reason solids don't fall through one another is because ______
of electrical forces.
Since boron has an atomic number of five, it has five _______
protons
The weight of matter comes mostly from it's ______
protons
Compared to the atoms that make up the body of an elderly person, the atoms that make up the body of a newborn baby are the _______
same age
Most alpha particles fired at gold foil pass through undeflected because _________
the atoms of gold, like any other, are mostly empty space