Physical Science Chapter 3
Give the number of protons, neutrons and electrons for the neutral copper isotope 65/29 Cu
29 protons, 36 neutrons, and 29 electrons
What is a way an ion cannot be formed?
An atom can lose a neutron
Is atomic mass, atomic number, mass number, or none of the above a weighted average?
Atomic mass
A chromium atom has twenty-four protons, twenty-eight neutrons, and twenty-four electrons. What is this atom's atomic number and mass number?
Atomic number= 24. Mass number= 52
If current models have shown the Bohr model of the atom to be inaccurate, why is the Bohr model of the atom still used today?
Because it is simple and easy to understand.
An ion that has more protons than electrons is called a ___________
Cation
Who thought of indivisible "atomos"?
Democritus
Who developed the nuclear model?
Earnest Rutherford
This subatomic particle is the smallest of the three subatomic particles.
Electron
True or False: An anion has a negative charge because it has lost an electron.
False
True or False: Aristotle first called the particles atomos, from which we get the word atom
False
True or False: Current atomic models show that electrons travel in distinct, spherical orbits around the nucleus.
False
True or False: Scientists currently hold to the quantum-mechanical model because it is able to pinpoint the locations of an atom's electrons.
False
Who developed the Saturnian model?
Hantaro Nagaoka
What does the 2- indicate in the oxygen ion O 2-
It has 2 extra electrons/ -2 charge
The Bohr model is still a widespread model not because...
It is still the most workable model to date
Who developed the plum pudding model?
J.J Thomson
Who first suggested that elements are made of atoms and that the atoms of an element are all alike?
John Dalton
This subatomic particle is found in the nucleus and has no electrical charge.
Neutron
This subatomic particle is the most massive of the three subatomic particles.
Neutron
Who believed that electrons move through spherical regions located a fixed distance from the nucleus?
Niels Bohr
The law of electrostatic charges states that____________________
Opposite electric charges attract each other and like electric charges repel each other.
One isotope of Phosphorus has fifteen protons and eighteen neutrons. What is the name of this isotope?
P-33
What is J.J Thomson's atomic model called?
Plum pudding model
The quantity of this subatomic particle in an atom of a substance determines the atom's identity.
Proton
This subatomic particle has a charge of +1e
Proton
Potassium- 39 and Potassium-41 have the same number of_______________
Protons
Silicon has three stable isotopes: Silicon-28, Silicon 29, and Silicon-30. Silicon's atomic mass is 28.085 u. Which isotope of Silicon is more common? Why?
Silicon-28. The atomic mass is closest to this isotope.
What observation did not lead Rutherford to believe that most of the atom's mass and positive charges were densely packed into a very small space?
Some alpha particles emitted photons as they fell back to their original energy levels.
Describe the plum pudding model
The plum pudding model consisted of the pudding as the nucleus/positively charged substance, with the chunks of fruit as the electrons/negatively charged chunks embedded in the positively charged substance.
True or False: John Dalton proposed that atoms are hard spheres of different sizes and masses
True
True or False: John Dalton thought that atoms are indivisible and cannot be destroyed.
True
True or False: Most of an atom consists of empty space.
True
True or False: Quantum mechanics deals with the behavior of matter and energy at the atomic and subatomic levels.
True
True or False: The quantum- mechanical model is the primary model used by scientists today.
True
How do you represent an atom that has lost/gained an electron?
You put a small + or - on the top right corner of the letter of the element, because when an atom loses/gains an electron, it creates a positive/negative charge, as there are more/less protons than electrons.
How would you write isotope notation?
You put the letter of the element in the middle with the atomic number on the top left and the atomic mass on the bottom left.
Describe two ways that an atom can become an ion. What are each of these ions called and what type of charge does each one have?
You take or add electrons. Cations are positive and anions are negative.
Experiments involving _____________ led to the discovery of the cathode ray.
alpha particles and gold foil
What atomic measurement is not typically represented with whole numbers?
atomic mass
The unique number of protons in the atoms of an element is that element's ____________
atomic number
J.J Thomson discovered the existence of the ________________
electron
Democritus suggested that matter_______________
existed in the form of very small, indivisible particles.
Atoms of the same element with differing numbers of neutrons are called _______________
isotopes
Carbon-14 is different from Carbon-12 in that is has a different amount of _____________
neutrons
The Bohr model show that electrons move...
only in distinct, spherical orbits at fixed distances from the nucleus.
The _________ is about 1836 times of an electron. The slightly more massive _____________ is about 1838 times the mass of an electron.
proton; neutron