Chapter 16 study guide
If an element contains 12 protons, its atomic number is BLANK.
12.
If 2 grams of element X combine with 4 grams of element Y to form compound XY, how many grams of element Y would combine with 14 grams of X to form the same compound?
28 grams.
Provide an analogy for an electron in an atomic orbital.
A bee trying to escape from a closed jar.
Describe John Dalton's model of the atom.
A tiny, solid sphere with a predictable mass for a given element.
In Rutherford's gold foil experiment, some of the BLANK aimed at gold atoms bounced back, suggesting that a solid mass was at the center of the atom.
Alpha Particles.
According to BLANK, all matter was made up of four elements- earth, air, fire, and water.
Aristotle.
The Greek philosopher Democritus coined what word for a tiny piece of matter that cannot be divided?
Atom.
Unlike Democritus, Aristotle did not believe that matter was composed of tiny, indivisible BLANK.
Atoms.
The moving blades of an airplanes propeller provide an analogy for the electron BLANK model.
Cloud.
John Dalton observed that elements always combine in the same ratio to form a particular BLANK.
Compound.
State Democritus' theory of the atom
Democritus thought that matter was made of tiny particles that could not be divided.
The region in which an electron is most likely to be found is called a(n) BLANK.
Electron cloud.
Which subatomic particle has a negative charge?
Electron.
Describe the arrangement of electrons in Bohr's atomic model.
Electrons travel around the nucleus in fixed energy's that vary from level to level.
In Bohr's model of the atom, BLANK move in fixed orbits around the nucleus.
Electrons.
when an atom gains or loses energy, some of its BLANK may move between energy levels.
Electrons.
Who provides evidence for the exsistence of a nucleus in an atom?
Ernest Rutherford.
An atom in which an electron has moved to a higher energy level is in a(n) BLANK state.
Excited.
TRUE/FALSE. An electron has the same amount of energy in all orbitals.
False.
TRUE/FALSE. Protons and Neutrons have the same charge?
False.
TRUE/FALSE. The number of protons is unique to any given element?
False.
When all electreons in an atom are in orbital with the lowest possible energy, the atom is in tis BLANK state.
Ground.
The glowing of a neon light is caused by electrons emitting energy as they move from BLANK and BLANK energy levels.
Higher and lower.
Oxygen 17 and oxygen 18 are both BLANK of oxygen.
Isotopes.
How is Bohr's atomic model similar to Rutherford's model?
It described a nucleus surrounded by a large volume of mass.
Describe Rutherford's model of the atom.
It is a huge stadium with a positively changed marble at the center.
The subatomic particle that J. J. Thomson discovered has a(n) BLANK charge.
Negative.
J.J. Thomson's experiments proved that an atom contained what type of charged particles?
Negatively charged particles.
The difference between a sample of heavy water and regular water and regular water is that a hydrogen atom in heavy water has an extra BLANK.
Neutron.
The mass of an isotope is the sum of its protons and BLANK.
Neutrons.
The nuclei of isotopes contain different numbers of BLANK.
Neutrons.
If an atom has an atomic mass of 23, can it have the same number of protons and neutrons?
No.
In Rutherford's gold foil experiment, what caused some of the alpha particles to bounce straight back from the gold foil?
Nuclei in the golds atoms.
Where is the subatomic particle with positive charge located?
Nucleus.
In Niels Bohr's model of the atom, electrons move about the nucleus like BLANK.
Planets orbiting the sun.
Rutherford's gold foil experiment provided evidence that the mass at the center of the atom was BLANK charged.
Positively.
What do scientists use to predict the locations of electrons in atoms?
Probability
What are the two atomic particles found in the nucleus?
Protons and neutrons.
Neutrons and BLANK have almost the same mass.
Protons.
The number of which atomic particle determines an atom's atomic number.
Protons.
What is the difference between an atom in the ground state and an atom in the excited state?
The atom in an excited state has more energy and is less stable than the atom in the ground state.
When an electron moves to a higher energy level, does the electron gain or lose energy?
The electron will gain energy.
What does the electron cloud model describe?
The most likely locations of electrons in atoms.
According to John Dalton;s observations, elements combine in a compound in what way?
The ratio of their masses is always the same.
TRUE/FALSE. An electron has far less mass than either a proton or neutron.
True.
How do you calculate the number of neutrons in an atom?
You subtract atomic number from mass number.
