Final exam Flashcards
(43 cards)
Who was the man who lived from 460B.C.–370B.C. and was among the first to suggest the idea of atoms?
Democritus
What was originally a tenet of Dalton’s atomic theory, but had to be revised about a century ago?
Atoms are tiny indivisible particles.
The mass of a neutron nearly equals the mass of a
___.
proton
The range in size of most atomic radii is approximately
5 x 10-11 m to 2 x 10-10 m
Who conducted experiments to determine the quantity of charge carried by an electron?
Millikan
The particles that are found in the nucleus of an atom are ____.
protons and neutrons
The atomic number of an element is the total number of which particles in the nucleus?
protons
The sum of the protons and neutrons in an atom equals the ____.
mass number
Isotopes of the same element have different ____.
numbers of neutrons
How is the number of neutrons in the nucleus of an atom calculated?
Subtract the number of protons from the mass number.
The atomic mass of an element depends upon the ____.
mass and relative abundance of each isotope of that element
About how many more times massive is a proton than an electron?
1,840
Who arranged the elements according to atomic mass and used the arrangement to predict the properties of missing elements?
Dmitri Mendeleev
Which subatomic particle plays the greatest part in determining the properties of an element?
electron
How does atomic radius change from top to bottom in a group in the periodic table?
It tends to increase.
What element in the second period has the largest atomic radius?
lithium
How does atomic radius change from left to right across a period in the periodic table?
It tends to decrease.
Atomic size generally ____.
increases as you move from left to right across a period
Which of the following elements has the smallest atomic radius?
chlorine
sulfur
selenium
bromine
chlorine
Electronegativity generally increases from ______________
left to right across a period.
Compared with the electronegativities of the elements on the left side of a period, the electronegativities of the elements on the right side of the same period tend to be ____.
higher
Which of the following decreases with increasing atomic number in Group 2A?
ionization energy
number of electrons
ionic size
shielding effect
ionization energy
In which group in the periodic table do the elements have the highest electronegativity values?
7A
In Bohr’s model of the atom, where are the electrons and protons located?
The electrons occupy fixed positions around the protons, which are at the center of the atom.
