Unit 2 chapter 2 Flashcards
1
Q
The smallest particle that has all the properties of an element
A
Atom
2
Q
Particles smaller than an atom
A
subatomic particles
3
Q
the ancient greeks believed all matter was a combination of four basic substances
A
earth, water,fire,air
4
Q
the four basic substances were combined in various proportions modified by four basic…..
A
essences
5
Q
what are the four basic essences
A
wet,dry,hot,cold
6
Q
how many elements identified today
A
118
7
Q
when was john dalton published
A
1808
8
Q
atoms can be classified according to what
A
atomic mass
9
Q
John Dalton described the atom as structures with various_____depending on what type of element it was
A
eyes and hooks
10
Q
Who arranged the first periodic table of elements?
A
Dmitri Mendeleev
11
Q
how were the elements arranged on the periodic table of elements?
A
in order of increasing atomic mass
12
Q
Elements were placed into how many groups?
A
8
13
Q
Each group was placed according to what?
A
similar in reaction and properties
14
Q
who described atoms as looking like plum pudding?
A
Thomson
15
Q
Bohr states that electrons traveled in….
A
precise fixed orbits
16
Q
fundamental particles of the atom
A
electrons, protons and neutrons
17
Q
the mass of an atom is expressed in
A
atomic mass units AMU
18
Q
contained in the nucleus-protons and neutrons
A
nucleons
19
Q
how many times larger are protons and neutrons than electrons
A
2000
20
Q
protons carry one unit of what charge
A
positive electric charge
21
Q
neutrons have what charge
A
no charge, electrically neutral
22
Q
the majority of an atom is made of what
A
empty space
23
Q
the majority of an atom’s mass is contained where
A
in its nucleus
24
Q
the number of protons in the nucleus determines what
A
the chemical element of the atom
25
atoms that have the same number of protons in the nucleus but differ in number o neutrons are
isotopes
26
electrons carry one unit of what
negative charge
27
electrons must be in certain
shells
28
each shell has a different
electron binding energy or energy level
29
the closer the electron is to the nucleus....
the greater the binging energy
30
what is the closest shell to the nucleus?
the k shell
31
the number o f electrons in the shells is equal to ...
the number of protons in the nucleus
32
if an atom has an extra electron or is lacking an electron it is what
ionized
33
an ionized atom has what kind of charge if it has an extra electron?
negative
34
an ionized atom has what kind of charge if it is missing an electron?
positive
35
an x-ray can create what by removing an orbital electron
ion pair
36
no atom can have more than how many electrons in its outermost shell
8
37
force that keeps an electron in orbit
centripetal
38
force that causes an electron to travel straight and leave the atom
centrifugal
39
caused by the attraction between a negative electron and a positive neutron
centripetal force
40
caused by the force of the traveling electron
centrifugal force
41
the strength of attachment of an electron to the nucleus
electron binding energy
42
shells which are _______to the nucleus have a greater binding energy
closer
43
the amount of energy necessary to ionize tissue atoms
ionization potential
44
a system or set of terms or symbols especially in a particular science
nomenclature
45
alphabetic abbreviation for an element
chemical symbol
46
the number of protons in an atom
Z-atomic number
47
the number of protons PLUS the number of neutrons in an atom
A- Atomic mass number
48
atoms that have the same atomic number of protons but different atomic mass number (nucleons)
isotopes
49
atomic mass number is equal to what?
the number of nucleons (neutrons and protons) in an atom and is always a whole number
50
act the same chemically but differ nuclearley
isotopes
51
AMU for Barium
Ba = 56
52
AMU for Tungsten
W = 74
53
atoms that have the same atomic mass number, but different atomic numbers
isobars
54
contain different numbers of protons and neutrons, but the same total number of number of nucleons
isobars
55
when radioactive isotopes break down, the original atom is called
parent atom
56
when radioactive isotopes break down, the resulting atoms are called
daughter atoms
57
as the atom decays, radiation is released in the form of what
alpha, beta and gamma particles
58
atoms that have the same number of neutrons, but the different number of protons
isotone
59
atoms that have the same atomic number and the same atomic mass number but are different structurally
isomer
60
atoms of various elements may combine to form these structures
molecules
61
The term “atom” was first used by the _____.
Greeks
62
The first person to describe an element as being composed of identical atoms was _____.
John Dalton
63
The smallest particle that has all the properties of an element is a(n) _____.
atom
64
The periodic table of the elements was developed by _____ in the late 19th century.
Mendeleev
65
Rutherford’s experiments in 1911 showed that the atom was composed of _____.
nucleus with an electron cloud
66
A positively charged nucleus surrounded by negatively charged electrons in well-defined orbits is the _____ model of the atom.
Bohr
67
What are the fundamental particles of an atom?
proton, neutron, electron
68
The chemical element is determined by the number of _____ in the atom.
protons
69
An atom in a normal state has an electrical charge of _____.
zero
70
The binding energies, or energy levels, of electrons are represented by their _____.
shells
71
When an atom has the same number of protons as another, but a different number of neutrons, it is called an _____.
isotope
72
When atoms of various elements combine, they form _____.
molecules
73
An atom that loses or gains one or more electrons is a(n) _____.
ion
74
The maximum number of electrons that can exist in an electron shell is calculated with the formula _____.
2n^r
75
A neutral atom has the same number of _____ and electrons.
protons and electrons
76
The innermost electron shell is symbolized by the letter _____.
k
77
The shell number of an atom is called the _____.
principal quantum number
78
The atomic number of an element is symbolized by the letter _____
Z
79
Aluminum has an atomic number of 13. How many protons does it have?
13. The atomic number equals the number of protons in an atom
80
Two identical atoms which exist at different energy states are called _____.
isomers
81
The atomic number of molybdenum is 42 and the atomic mass number is 98. How many neutrons does it have?
56. The number of neutrons is equal to A–Z
82
A chemical compound is any quantity of _____.
one type of molecule
83
During beta emission, an atom releases _____.
electrons
84
The only difference between x-rays and gamma rays is their _____.
origin
85
The _____ is the least penetrating form of ionizing radiation.
alpha particle
86
An electron is ____ charged and has a mass of ____ amu(s).
negatively; 0.000548
87
The orderly arrangement of elements in the periodic table is based upon
atomic number.
88
The sum of protons and neutrons in a nucleus is called the
mass number
89
Carbon has an atomic number of 6. One of its isotopes has a mass number of 14. The number of neutrons in this isotope is
8
90
Isotopes have ____ mass numbers and ____ atomic numbers.
different; the same
91
The atomic number is the number of ____ contained in the nucleus
protons
92
An isotope of boron has 5 protons and 6 neutrons. The atomic number of boron is
5
93
An element with an atomic number of 22 has how many electrons in the second principal quantum number level (L shell)?
8
94
The nuclear particles that distinguish one element from another are the
protons
95
An atom has an atomic number of 18 and a mass number of 38. Letting P = the number of protons and N = the number of neutrons, which of the following atoms is the isotope of this atom?
P = 18, N = 21
96
If an electron is gained or lost from an atom, that atom becomes
ion
97
The atomic number of an atom is determined by those particles that have an atomic mass unit of 1 and a single postiive charge called
protons
98
The majority of the mass of the nucleus is derived from
protons and neutron only
99
A neutral atom that loses an electron by ioinization is termed a:
positive ion
100
The centralized portion of an atom, the nucleus, is primarily composed of particles called the:
1. neutrons
2. electrons
3. protons
4. nucleons
1,3 & 4
101
The chemical bond formed when two or more atoms share electrons is termed:
covalent bonding
102
The following radiation can only be emitted from heavy elements:
alpha
103
Arrange in order from smallest to largest
1. proton
2. molecule
3. electron
4. atom
5. cells
3,1,4,2,5
104
What is the term for a nucleus that spontaneously emits particles and energy and transforms itself into another atom
radioactive disinigration and radioactive decay
105
If the radioactive half-life of a material is 8 years, what percentage of the material will be present after 64 years?
0.4%
106
Which form of ionizing radiation is most pentrating?
gamma
107
In a neutral atom the electrical neutrality is acheived by maintaining a balance between the:
protons and electrons
108
Which of the following fundamental particles has the lowest atomic mass?
electron
109
The maximum number of inner shell electrons in any atom is:
2
110
Nuclides thaving the same atomic number but different atomic masses are termed:
isotopes
111
An electron with the lowest binding energy is most likely located in the
M-Shell
