Which of the following models of the atom reflects the unpredictable motion of the electron?
|B)||solid ball the same throughout|
|C)||ball of raisin-cookie dough with raisins representing electrons|
|D)||small ball within a large shell containing empty space|
An atom containing six positive charges and six negative charges has __________ charge.
|A)||a strong negative|
The __________ of an element is the number of __________ of an atom of that element.
|A)||atomic mass, electrons in the nucleus|
|B)||atomic number, protons in the nucleus|
|C)||mass number, protons plus neutrons in the outermost energy level|
|D)||mass number, neutrons in the nucleus|
The atomic mass of an element is __________ of that element.
|A)||the number of electrons in each atom|
|B)||the number of protons plus the number of neutrons of an atom|
|C)||the average mass of an atom|
|D)||the number of protons in each atom|
__________ are atoms of the same element that have different numbers of neutrons.
Which of the following is the correct chemical symbol for carbon?
The discovery of the sixth quark was accomplished by __________.
|A)||experimenting with a cathode ray tube|
|B)||using the Hubble Space telescope|
|C)||studying proton collisions|
|D)||bombarding gold foil with alpha particles|
Atoms consist of a positively charged center called a(n) __________.
Scientists have broken down protons and neutrons into smaller particles called __________.
Aristotle believed that matter was __________.
|B)||capable of being broken down into smaller parts|
|C)||composed of atoms|
|D)||composed of molecules|
Democritus believed that the universe was made of empty space and __________.
A(n) __________ is a method of representing atoms and the electrons in their outer energy levels.
|A)||electron dot diagram|
The __________ is a chart created by chemists to organize the elements according to repeated changes on properties.
The mass of a proton is measured in __________.
|A)||atomic mass units|
Who formed the first periodic table?
Which of the following best describes the three general groups of elements?
|A)||metals, metalloids, and synthetics|
|B)||solid, liquid, and gas|
|C)||metals, nonmetals, and noble gases|
|D)||metals, metalloids, and nonmetals|
Which of the following atomic particles is positively charged?
Which of the following methods would be most useful for describing atoms?
|A)||touching with bare hands|
|B)||constructing a model|
|C)||visualizing with a microscope|
|D)||observing in a test tube|
The atomic number of manganese is 25; its mass number is 55. How many neutrons does an atom of manganese have in its nucleus?
The __________ of an atom is the number of neutrons plus protons.