Flashcards in Atom Deck (73):
1
Anything that takes up space and has mass
Matter
2
Quantity of matter in a body regardless of its volume or any forces acting on it
Mass
3
Measure of the force of gravity acting on it
Weight
4
Building blocks of matter
Atoms
5
Particles much smaller than atoms
Subatomic particles
6
How many elements have been identified ?
112
7
Naturally-occuring elements
92
8
Artificially - produced elements
20
9
He named the smallest piece of matter "atomos"
Democritus
10
Meaning "not to be cut" / indivisible
Atomos
11
They favored the earth, fire , air and water to the nature of matter
Aristotle and Plato
12
Laid the foundation for modern atomic theory
John Dalton (1808)
13
Atoms can't be subdivided , created or destroyed
Modern Atomic Theory
14
Formed by joining of atoms of two or more elements
Compounds
15
Dalton's atom had _________ to account for chemical combination
Hooks and eyes
16
Atoms of different elements combine in simple whole number ratios to form chemical compounds
Law of multiple proportions
17
He is concerned with the investigations of the electrons ( cathode rays)
Joseph John "J J" Thompson
18
Concluded that "electrons were an integral part of all atoms"
JJ Thompson
19
Thomson proposed a model of the atom that is called
Plum Pudding
20
Negatively charged that is also known as electrons
Corpuscles
21
Introduced the nuclear model of the atom
Discovered the nucleus
Ernest Rutherford
22
Proposed the planetary model
Niels Bohr
23
He proposed the wave-particle duality
Louis de Broglie
24
All particles of matter moving at some velocity would have the properties of a wave
Particle- Wave Duality
25
He created the quantum mechanical model of the atom
Erwin Schrodinger
26
The probability of finding the electron is the greatest
The cloud is most dense
27
Nucleus is sorrounded by an electron cloud
This model intoduced the concept of sub- energy levels
Quantum mechanical model
28
Electrons do not move about an atoms in a definite path like the planets around the sun
Wave mechanics theory
29
Atom has small positively charged nucleus surrounded by a large region where there are electrons (negative ) to make the atom neutral
Modern Atomic atomic model
30
Created the quantum mechanics
Werner Heisenberg
31
Diameter of the atom
0.1 - 0.5 nm
1 x 10^-10 m to 5x 10^-10
32
Fundamental particles of the atom
Protons
Neutrons
Electrons
33
Positively charge particle
Proton
34
Mass of proton
1.67 x 10 ^-24 g
1.67 x 10 ^-27 kg
35
Amu of proton
1.007316
36
Discovered proton
Ernest Rutherford (1920)
37
Negative charged particles
Electron
38
Mass of electron
9.1 x 10^-28 g
9.1 x 10^- 31 kg
39
Amu of electron
0.000549
40
Discovered electrons
Joseph John Thompson (1897)
41
Particle with no electrical charge
Neutron
42
Mass of neutron
1.675 x 10 ^ -24 g
1.675 x 10^ - 27 kg
43
Amu of neutron
1.008701
44
Discovered neutron
Sir James Chadwick (1932)
45
Center of an atom
Nucleus
46
Protons and neutrons were collectively known as
Nucleons
47
Determines the chemical element
Number protons
48
Removal of an electron from the atom
Ionization
49
An atom that carries an electrical charge
Ion
50
Positive ion
Cation
51
Negative ion
Anion
52
A cation and anion simultaneously produced
Ion pair
53
To determine the max no of electron per shell
2n^2
54
Shell number n
Principal quantum number
55
Force toward the center
" center -seeking"
Centripetal force
56
Force away from the center
"Center fleeing"
Centrifugal force
57
Strength of an attachment of an electron to the nucleus
Electron Binding Energy (Eb)
58
Combining capacity of an atom of an element
Valency
59
Electrons present in the outmost shell of the atom
Valence electrons
60
List of all the elements that can build matter
Periodic table
61
Arranged the elements according to the number of atomic mass
Dmitri Mendeleev
62
Number of protons in an atom
Atomic number (z)
63
Sum of the protons and neutrons in an atom
Atomic mass ( A)
64
Number of protons is equal to the numebr of the electrons
Neutral atom
65
Atomc species characterized by specific constitution of the nucleus
Nuclide
66
Nuclide is proposed by
Truman P. Kohman
67
Atoms having same element , same protons but different mass
Isotopes
68
Atoms with different element , same number of mass
Isobar
69
Same neutron number , different proton number
Isotones
70
Metastable state of an atomic nucleus cause by excitation
Isomer
71
Usually restricted to refer to isomers with half lives of 10^-9 seconds or longer
Metastable state
72
Atoms of various elements may combine to form structure
Molecules
73