Quiz 3 Flashcards
is everything that occupies space and has mass.
Matter
are the basic unit of matter.
Atoms
is the smallest unit of matter that retains all of the chemical properties of an element. It combine to form molecules, which then interact to form solids, gases, or liquids. For example, water is composed of hydrogen and oxygen atoms that have combined to form water molecules.
atom
5 phases of matter
Solid, liquid, gas, plasma, bose einstein condensate
Proposed one of the first theories that attempted to describe the things around us. He argued that all matter was composed of four elements: fire, air, water, earth. That the ratio of these elements affected the properties of matter.
EMPEDOCLES (492 BCE-432 BCE)
1 atom=
1 element
2 or more atoms =
Molecules (compound)
His ideas were based on reasoning rather than science
DEMOCRITUS (460-370 BCE)
He reasoned that if you continue to cut a material into smaller pieces until you reach a piece that is so tiny it could no longer be divided.
DEMOCRITUS (460-370 BCE)
He called the infinitely small pieces of matter “atomos”, meaning indivisible.
DEMOCRITUS (460-370 BCE)
Democritus called the infinitely small pieces of matter___ meaning ____.
“atomos”, indivisible
An English chemist who made an elaboration about these atoms
John Dalton (1808)
He introduced the Billiard Ball Model of an atom.
John Dalton (1808)
He created the first Atomic theory which consisted of these main points:
Atomic Theory
- All matter is composed of extremely small particles called atoms.
- Atoms of a given element are identical in size, mass, and other properties.
- Atoms of different elements differ in size, mass and other properties.
- Atoms cannot be subdivided, created, or destroyed.
- Atoms of different elements can combine in simple whole number ratios to for chemical compounds.
John Dalton (1808)
Discovered the negatively charge particle (electron) in an atom. Symbolized by e or B in 1897.
Sir Joseph John Thomson (1890’s)
He proposed the ‘Plum Pudding Model’ or ‘Chocolate chip Model’ of an atom.
This model suggested that atoms were a large positive sphere with negative electrons embedded into it.
Sir Joseph John Thomson (1890’s)
This model suggested that atoms were a large positive sphere with negative electrons embedded into it.
Plum Pudding Model’ or ‘Chocolate chip Model’
He discovered that an atom has a nucleus and positively charge particle (protons) through his Gold Foil experiment.
Ernest Rutherford (1911)
He proposed the ‘Nuclear Model” of an atom.
Ernest Rutherford (1911)
Proposed the “Atomic Planetary Model”
This model suggested that electrons orbited the nucleus in levels which he called shells or orbits
Niels Bohr (1913)
This model suggested that electrons orbited the nucleus in levels which he called shells or orbits
Atomic Planetary Model”
Proposed the quantum mechanical model of the atom
This model assumes that the electron is a wave and tries to describe the regions in space, or orbitals, where electrons are most likely to be found.
Erwin Schrödinger (1926)
This model assumes that the electron is a wave and tries to describe the regions in space, or orbitals, where electrons are most likely to be found.
quantum mechanical model
refers to the constitution of its nucleus and the arrangement of the electrons around it.
Atomic structure
make up the nucleus of the atom, which is surrounded by the electrons belonging to the atom.
The protons and neutrons
___of an element describes the total number of protons in its nucleus.
atomic number
Neutral atoms have _____ However, atoms may gain or lose electron in order to increase their stability, and the resulting charged entity is called an ion.
equal numbers of protons and electrons.
atoms may gain or lose electron in order to increase their stability, and the resulting charged entity is called an
Ion
is a method of showing the chemical elements in a table with the elements arranged in order of increasing atomic number. Most of the work that was done to arrive at the periodic table that we know can be attributed to Dmitri Ivanovich Mendeleev
Periodic table of elements
Most of the work that was done to arrive at the periodic table that we know can be attributed to
Dmitri Ivanovich Mendeleev
Is a horizontal row in the periodic table.
period
The elements in a period have the_______.
same number of electron shells
____is a column in the periodic table which is important in classifying elements.
group
The elements in a group have similar physical or chemical characteristics of the
“valence electron” or the outermost shell.
is the measure of the size of an atom.
Atomic Radius
is the energy needed to remove an electron from an atom in the gas phase. It is different for each element.
lonization energy
can be thought of as how much an element wants electrons.
Electron Affinity
It is the tendency of atoms to attract electrons.
Electronegativity
Sir Joseph John Thomson discovered the negatively charge particle ________ in an atom. Symbolized by e or B in 1897.
electron
How many period are in the horizontal row of the periodic table of elements?
7 periods
How many groups are in the vertical row of the periodic table of elements?
18 groups
Atomic Theory of john dalton
- All matter is composed of extremely small particles called atoms.
- Atoms of a given element are identical in size, mass, and other properties.
- Atoms of different elements differ in size, mass and other properties.
- Atoms cannot be subdivided, created, or destroyed.
- Atoms of different elements can combine in simple whole number ratios to for chemical compounds.
Electron is Symbolized by
e or B in 1897.
water is composed of____ that have combined to form_____
hydrogen and oxygen atoms, water molecules.
Periodic table of elements is a method of showing the chemical elements in a table with the elements arranged in
order of increasing atomic number
atoms may ____ in order to increase their stability, and the resulting charged entity is called an ion.
gain or lose electron
The quantum mechanical model assumes that the electron is a wave and tries to describe the regions in _____, where ____ are most likely to be found.
space, or orbitals, electrons
Ernest Rutherford (1911) discovered that an atom has a nucleus and positively charge particle (protons) through his
Gold Foil experiment
Ernest Rutherford (1911) discovered that an atom has a _____ (protons) through his gold foil experiment
Nucleus and positively charged particles
In the gold foil experiment electricity passes from the ____ to the _____
cathode, anode
a small bit of electricity passes through the hole in the
anode
what are the two metal plate?
positively charged and negatively charged metal plate
In niels bohr “atomic planetary model” the sun symbolized the____ and the planets symbolized the____
Nucleus, electrons
Atomic radius ____ in The Periodic Table as you move from
Decreases, left to right across a period
Ionization Energy _____ in The Periodic Table as you move from
Increases, left to right across a period
Electron affinity_____ from _____
decreases (becomes more negative) ,left to right within a period.
Electronegativity ____ in The Periodic Table from
increases, left to right across periods
Forst model to assign a specific inner structure to an atom
Plum pudding model
The quantum mechanical model uses a quantum numbers to define the atomic orbitals and their electron distributors
Quantum numbers and atomic orbitals
Describes an electron’s energy level and average distance from nucleus
Principal quantum number (n)
Determines the shape of the orbital, whether it is a spherical s-orbital, dumbbell-shaped, p-orbital, clover-shaped d-orbital and so on.
Angular Momentum Quantum Number
Indicates the spatial orientation lf orbitals and varies from -1 to 0 to +1 based on the value of 1.
Magnetic quantum numbers
Describes an electron’s spin in a magnetic field as either+1/2 (clockwise) or -1/2 (counterclockwise)
Spin quantum number
