Mastering physics CH 11
A nucleon has a mass of about
1 atomic mass unit (amu)
What is the molecular mass of a water molecule?
18 amu
How many different kinds of elements are in a water molecule?
2
How many protons should be added to the nuclei of oxygen atoms so the resulting gas will glow red when an electric current is in it?
2
How many atoms are in this carbohydrate molecule, C6H12O6?
24
The atomic masses of two isotopes of cobalt are 59 and 60. What is the number of protons in each? What is the number of neutrons in each? What is the number of orbiting electrons in each when the isotopes are electrically neutral?
27 each 32, 33 27 electrons
The number of atoms in a common water molecule is
3
How many shells are represented in the presently known periodic table?
7
If a gram of antimatter meets a kilogram of matter, the amount of mass to survive is
999 grams
How does a molecule differ from an atom? Give an example.
A molecule is composed of two or more atoms bonded together: H2O.
What is meant by the term nucleon?
A proton or neutron
Rank the number of shells in these noble-gas atoms from most to least: A. Xenon. B. Krypton. C. Helium. D. Neon.
A, B, D, C
Who first explained Brownian motion and made a convincing case for the existence of atoms?
Albert Einstein
The periodic table of the elements is a list of
Atoms
Why can't atoms be seen with a powerful optical microscope?
Atoms are much smaller than a wavelength of light.
What is a compound? Cite two examples.
Atoms of different elements with bonds between them: NaCl and H2O
What is a mixture? Cite two examples.
Atoms pressed together without bonding: air and salt and sand
A pair of helium nuclei fused together produces
Berylium
Which of these atoms has the greatest number of electrons? a. gold b. carbon c. uranium d. helium e. iron
C
What are the five most common elements in humans?
C, H, O, N, and Ca
If two protons and two neutrons are removed from the nucleus of an oxygen atom, what nucleus remains?
Carbon
Two protons removed from an oxygen nucleus result in
Carbon
What causes dust particles and tiny grains of soot to move with Brownian motion?
Collisions with invisible molecules
Heavy atoms are not appreciably larger in size than light atoms because the nuclei of heavy atoms have more
Electric charge
Which atom is negatively charged?
Electrons
Since atoms are mostly empty space, why don't we fall through a floor we stand on?
Electrons in one atom repel the electrons in another.
How does the electric charge of a proton compare with the electric charge of an electron?
Equal and opposite
To become a negative ion, does an atom lose or gain an electron?
Gains
What is the evidence that dark matter exists?
Gravitational forces within galaxies are too great to be accounted for with ordinary matter.
A pair of hydrogen nuclei fused together produces
Helium
One neutron added to a helium nucleus results in
Helium
What element has the lightest atoms?
Hydrogen
What is the most abundant element in the known universe?
Hydrogen
Where in the atom is most of its mass concentrated? What is this mass composed of?
In the nucleus as protons and neutrons
How does one isotope differ from another?
It has a different number of neutrons.
Who advanced the idea of atoms in the early 1800s?
John Dalton
To become a positive ion, does an atom lose or gain an electron?
Loses
Are most of the atoms around us younger or older than the Sun?
Most are older than the Sun
The charge in the nucleus of an antimatter hydrogen atoms is
Negative
If a nitrogen atom and a slightly heavier oxygen atom have equal kinetic energies, which has the greater average speed?
Nitrogen
If no molecules in a body could escape, would the body have any odor?
No
How are most of the elements with nuclei heavier than those of hydrogen and helium formed?
Nuclear fusion in stars
Which is the smallest particle?
Quark
What element results if two protons and two neutrons are ejected from a radium nucleus?
Radon
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
Same age
Why aren't heavier elements much larger than lighter elements?
The larger positive charge in the nucleus pulls the electrons into closer orbits.
What does the atomic number of an element tell you about the element?
The number of protons in its nucleus
How does the approximate number of atoms in the air in your lungs compare with the number of breaths of air in Earth's atmosphere?
The numbers are the about the same, 10^23.
Why can atoms be seen with an electron beam?
The wavelength of the electrons is smaller than an atom.
What occurs when a proton and an antiproton meet?
They annihilate each other.
Which contains more atoms? a. 1 kg of hydrogen b. 1 kg of iron c. both contain the same
a
Which of the following statements is true? a.molecules are the smallest subdivision of matter that still retain a substance's chemical properties b. molecules form atoms that determine chemical properties of a substance c. a molecule is the smallest existing particle chemical elements are made up of about 100 distinct molecules d none of the above
a
Nuclei of atoms that make up a newborn baby were manufactured in
ancient stars
Which of the following is NOT a compound? a. ammonia b. air c. salt d. water e. all are compounds
b
Atoms can be photographed by a. electron beams. b. scanning electron microscopes. c. both of these d. neither of these
c
The difficulty of taking a photograph of an atom with light is a. unwanted diffraction. b. that atoms are smaller than wavelengths of light. c. both of these d. neither of these
c
Which is the lightest particle? a.neutron b.proton c. electron d. all about the same
c
Which of the following elements has the most mass? a.hydrogen b. iron c. uranium d. lead e. all have the same mass
c
Which of the following is an element? a. Carbon dioxide b. A supernova c. Hydrogen d. H2O
c
Which of the following statements is true? A. there are thousands of different kinds of atoms that account for a wide variety of substances B. a large atom can be photographed with the aid of an ordinary microscope C. there are only about 100 different kinds of atoms that combine to form all substances D. an atom is the smallest particle known to exist E.none of the above
c
Which of these atoms has the greatest amount of electrical charge in its nucleus? a. gold b. carbon c. uranium d. helium e. iron
c
Which of these atoms has the largest number of neutrons in the nucleus? a. Carbon b. Hydrogen c. Helium d. Gold
d
Which of these has the greatest number of protons in its nucleus? a. gold b. mercury c. silver d. lead
d
Which of the following is NOT a mixture? a. cake b. beach sand c. air d. granite e. none of the above
e
A force that determines the chemical properties of an atom is
electrical force
The chemical properties of matter are due mostly to their
electrons
The volume of matter is due mostly to its
electrons
The element gold contains
gold atoms
An isotope is simply an atom that
has different numbers of neutrons for the same element.
A granite block is mostly empty space because the atoms in the granite are
mostly empty space themselves.
Mass number refers to the number of
nucleons in the nucleus
Although solid matter is mostly empty space, we don't fall through the floor because
of electrical forces.
The number of protons in a neutral atom is balanced by an equal number of
orbital electrons
Brownian motion is caused by
particles larger than atoms bumping into them.
Dark matter is considered to be
plentiful in the universe
An element is distinct because of its number of
protons
Atomic number refers to the number of
protons in the nucleus
Heavier atoms are not proportionally larger than lighter atoms due to the greater number of protons
pulling surrounding electrons into tighter shells.
When carbon and oxygen atoms combine, energy is
released by the reaction
Assuming all the atoms exhaled by Julius Caesar in his last dying breath are still in the atmosphere, we breathe in at least one of them each
single breath
If we doubled the magnifying power of the most powerful optical microscope in the world, we would
still not be able to see or photograph an atom.
Atoms heavier than helium were at one time manufactured by
thermonuclear fusion.